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4 years, 9 months ago

Challenges to eradicate cervical cancer globally

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  • Experts have called for the worldwide eradication of cervical cancer, but this is not likely to happen for a long time
  • Significant progress has been made to eliminate cervical cancer in developed countries
  • The overwhelming burden of cervical cancer falls disproportionately on women in low- to middle-income countries (LMIC)
  • LMIC have relatively low levels of awareness of cervical cancer, patchy prevent programs and limited treatment options
  • Over 80% of cervical cancer cases and deaths occur in LMIC
  • Cervical cancer is the fourth most common cancer in women worldwide
  • In 2018 there were an estimated 680,000 new cases and 311,000 deaths from the disease worldwide
  • Cervical cancer is caused by sexually acquired infection from high-risk strains of the human papilloma virus (HPV)
  • The majority of women will be infected with HPV at some point in their life
  • HPV also causes genital warts and cancers of the head and neck and is also linked to cancers of the anus, vulva, vagina, penis and oropharynx
  • HPV vaccines protect against 70% of cervical cancers and about 90% of genital warts
  • Regular screening is also recommended to reduce the incidence of cervical cancer
 
Challenges to eradicate cervical cancer globally

Cervical cancer is a killer disease, which only affects women. It affects women of all ages from schoolgirls to grandmothers, but it is significantly more prevalent between the ages of 30 and 45.
 
The cervix, also known as the neck of the womb, connects a woman's womb and her vagina.
 
Lancet study raises hope of eradicating cervical cancer
 
Research findings published in the June 2019 edition of The Lancet suggest that HPV vaccination, which has been available to adolescent girls in wealthy developed countries since 2007, has led to a dramatic reduction in the number of HPV infections, precancerous cervical lesions and anogenital warts and provides hope of eradicating cervical cancer. Marc Brisson, Professor in the Department of Social and Preventative Medicine, Laval University, Canada, who led the research - a meta-analysis of over 65 former studies covering 60m people - said: "We will see reductions [in cervical cancer] in women aged 20-30 within the next 10 years, and eradication  of the disease [defined as <4 cases per 100,000] might be possible if sufficiently high vaccination coverage can be achieved and maintained". Over the past two decades, the incidence rates of cervical cancer in developed countries have fallen significantly, and between 1955 and 1992, the incidence rate of the disease decreased 70% in the US. These falls are attributed to effective nationwide screening.
 
Epidemiology

Cervical cancer is the fourth most common cancer in women worldwide and second for women between 15 and 44. In 2018 there were an estimated 680,000 new cases and 311,000 deaths from the disease worldwide. The overwhelming majority of cases are caused by two specific strains of the human papilloma virus (HPV). HPV infection and early cervical cancer typically do not present noticeable symptoms, and cervical cancer may take 20 years or longer to develop after an HPV infection. The overwhelming global burden of the disease falls disproportionately on women in low- to middle income countries (LMIC). There is a significant and growing gap in the incidence and mortality rates of cervical cancer between developed nations and LMIC. Despite international efforts, it seems unlikely that this gap will be narrowed in the medium term.
 
In this Commentary
 
This Commentary describes the spread of HPV, the vaccines developed to prevent infection from specific high-risk strains of the virus and recommended vaccination regimens. We describe the nature and significance of complementary screening programs and present evidence to suggest that women who fail to get screened are more likely to contract cervical cancer in later life than women who are screened. HPV vaccination programs are more prevalent in developed economies and are associated with a significant reduction in the incidence rates of cervical cancer. This suggests that the battle to eliminate cervical cancer is being won in some wealthy developed nations. Australia is positioned to become the first country in the world to eliminate cervical cancer. Despite substantial global efforts to reduce the incidence rates of cervical cancer, the gap in preventing, diagnosing and treating the disease between wealthy nations and LMIC is significant and growing. We conclude by suggesting that to eradicate cervical cancer, screening and prevention programs must be linked to easily accessible and effective treatment.
 
The spread of HPV
 
Over 70% of cervical cancer is caused by two high-risk strains of HPV. Most women will contract HPV at some stage during their life, but this usually clears-up on its own without the need for any treatment. HPV is most commonly spread during vaginal, anal or oral sex. The virus can be passed even when an infected person has no signs or symptoms. If you are sexually active you can get HPV, even if you only have sex with one partner. Notwithstanding, the risk increases with the number of new sexual partners and their sexual histories. You also can develop symptoms years after you have sex with someone who is infected. This makes it hard to know when you first became infected.
  
HPV vaccines
 
The US Food and Drug Administration (FDA) has approved three vaccines, which prevent infection with disease-causing HPV types. These are Gardasil, Gardasil 9 and Cervarix. All three vaccines prevent infection with HPV types 16 and 18 in women who have not already been infected by these types. These are two high-risk HPV’s that cause about 70% of cervical cancers and an even higher percentage of some of the other HPV-caused cancers. Gardasil also prevents infection with HPV types 6 and 11, which cause 90% of genital warts. Gardasil 9 prevents infection with the same four HPV types, plus five additional cancer-causing types.
 
About 79m Americans are currently infected with HPV, with roughly 14m people becoming newly infected in the US each year. In the UK, HPV is present in one in three people and 90% of individuals will come into contact with some form of the virus in their lifetime. About 80% of sexually active people are infected with HPV at some point in their lives, but most people never know they have the virus. Whitfield Growdon, a surgical oncologist at the Massachusetts General Hospital and professor at the Harvard University Medical School describes the HPV vaccination as, “one of the most meaningful interventions for reducing cervical cancer”; see video below.
 
 
Who should get vaccinated?

All girls and boys aged between 11 and 12 should get the HPV vaccination. Every year in the US, over 13,000 males contract cancers caused by HPV. Catch-up HPV vaccines are recommended for girls and women through the age of 26, and for boys and men through the age of 21, if they did not get vaccinated when they were younger. HPV vaccination is also recommended for the following people, if they did not get vaccinated when they were younger: (i) young men who have sex with men through the age of 26, (ii) young adults who are transgender through the age of 26 and (iii) young adults with certain immunocompromising conditions (including HIV) through the age of 26.
 
Early cervical cancer is asymptomatic
 
Because early cervical cancer is asymptomatic, it is important for women to have regular Papanicolaou (Pap) smears - also called Pap tests - to detect any precancerous changes in the cervix that might lead to cancer. This is in addition to the HPV vaccination. In England women are invited to have Pap smears every three years between the ages of 25 and 49, when rates of cervical cancer are at their peak, and every five years between 50 and 65. Other international screening guidelines recommend that women aged 21 to 29 have a Pap smear every three years. Women aged 30 to 65 are advised to continue having a Pap test every three years, or every five years if they also combine it with an HPV DNA test. Women over 65 can stop testing if they have had three consecutive normal Pap tests, or two HPV DNA and Pap tests with no abnormal results.
 
The HPV DNA test determines the most likely cause of cervical cancer by looking for pieces of DNA in cervical cells and is recommended for women over 30 and not for women under 30. This is because women in their 20s tend to be more sexually active and therefore are more likely (than older women) to have an HPV infection that will go away on its own. Results of an HPV DNA test carried out on a woman in her 20s is not as significant as in and older woman and also may be confusing. The HPV DNA test can also be used in women who have slightly abnormal Pap test results to find out if they might need more testing or treatment.
 
The Pap smear/test
 
The Pap smear or Pap test is a method of cervical screening used to detect potentially precancerous and cancerous processes in your cervix. During the routine procedure, cells from your cervix are gently scraped away and then examined for abnormal growth. Abnormal findings are often followed-up by more sensitive diagnostic procedures and if warranted, by interventions that aim to prevent progression to cervical cancer. Detecting cervical cancer early with a Pap smear significantly increases the chances of a cure. A Pap smear can also detect changes in your cervical cells, which suggest you might develop cancer in the future. In the two videos below Growdon describes the Pap smear and other tests for diagnosing cervical cancer.
 

What is a Pap smear test?
 
 
Diagnostic tests for cervical cancer
 
 Women failing to have the Pap test are 6-times at greater risk of cervical cancer
 
There is evidence to suggest that women over 50 who fail to have a regular Pap smear have a much higher risk of developing cervical cancer compared with other women the same age who have a history of regular screening. Research carried out by Cancer Research UK and reported in 2014 investigated the utility of regular cervical cancer screening after 50, and whether 64 was an appropriate age to stop screening and concluded “yes” and “yes”. The study compared the screening history of 1,341 women between 65 and 83 in England and Wales who were diagnosed with cervical cancer over a five-year period, with 2,646 women of the same age without the disease. Findings suggest that women who did not attend screening tests were six times more likely to develop cervical cancer between 65 and 83 compared with women that did. 
 
Australian the first country to eradicate cervical cancer
 
Australia is well positioned to become the first country in the world to eradicate cervical cancer. This is largely due to national vaccination and screening programs, which could see the disease effectively eliminated as a public health issue within the next two decades. In 2007, Australia launched a national publicly-funded school immunisation program to reduce HPV, which complemented a national  cervical cancer screening program that was launched in the 1990s. These have been shown to reduce the incidence of cervical cancer and significantly increase early diagnosis when the disease is curable.
 
A research paper about the Australian initiative published in the January 2019 edition of The Lancet Public Health concludes that, “the annual incidence of cervical cancer in Australia is likely to decrease to fewer than six new cases per 100 000 women by 2020 (range 2018–22) and to fewer than four cases per 100 000 women by 2028 (2021–35). The annual incidence of cervical cancer could decrease to one new case per 100 000 by 2066 (2054–77) if the existing HPV-based screening program continues in cohorts who are offered the nonavalent vaccine”; [a nonavalent vaccine works by stimulating an immune response against nine different antigens, such as nine different viruses or other microorganisms]. According to Suzanne Garland, Professor and Clinical Director of Microbiology and Infectious Diseases at the Royal Women’s Hospital, Melbourne, Australia, who led the research, “within 40 years the number of new cases of cervical cancer [in Australia] is projected to drop to just a few”.
 
The two worlds of cervical cancer
 
Global efforts to reduce the incidence rates of cervical cancer have focused on HPV vaccination  and the Pap test. Although experts are optimistic about eliminating cervical cancer in developed nations, which have advanced healthcare systems and extensive HPV vaccination, screening and treatment programs, they are significantly less sanguine about eradicating the disease in LMIC where there are relatively low levels of awareness of cervical cancer, a dearth of  preventative strategies, limited expertise and a narrow band of treatment options. This results in the disease being identified late when it is at an advanced stage, which leads to higher rates of morbidity and death. Indeed, 85% of all cases and cervical cancer deaths occur in LMIC, where the death rate is 18 times higher than in wealthy nations.
 
Cervical cancer a challenge for LMIC
 
The gap in preventing, diagnosing and treating cervical cancer between wealthy nations and LMIC is  described in a paper published in the November 2017 edition of Gynecologic Oncology Reports and suggests that, “Developing countries continue to bear a disproportionate percentage of the global cervical cancer burden. Investigations into the growing gap in incidence and mortality between developed nations and LMIC have cited persistent financial, infrastructural and educational limitations as key drivers. Pervasive lack of access to both preventative and definitive care has left a substantial portion of cervical cancer patients with minimal options for disease management”.
 
WHO strategy to eliminate cervical cancer
 
Recognising this disparity, in 2018, the Director-General of the World Health Organization (WHO) announced a call to action for the eradication of cervical cancer as a public health problem. In January 2019, the Executive Board of the WHO requested the Director General to develop a draft strategy to accelerate cervical cancer elimination, with clear targets for the period 2020 - 2030.
 
Vaccination and screening must be linked to effective therapies
 
The expansion of screening programs for cervical cancer in LMIC is only part of the answer to closing the gap with developed nations and eradicating cervical cancer globally. It is imperative that screening is linked to increased access to effective treatment for women with cervical cancer, particularly in its early stages when it is still curable.  In LMIC there is often not only reduced access to preventive HPV vaccines and screening, but limited access to treatment and trained personnel. Notwithstanding, there is evidence to suggest that, in LMIC less-invasive and less–resource-intensive treatment options can be effective and are increasingly being made available.
 
Late presentation of cervical cancer in LMIC
 
Women from LMIC generally seek treatment for cervical cancer only after the presentation of symptoms when the disease is advanced and challenging to treat. Also, they often lack awareness of the disease and ways to prevent it. Further, in some regions of the world, cultural norms and myths about cervical cancer pose additional barriers to prevention. Despite such obstacles, the disease can be prevented at low cost by healthcare providers employing relatively simple techniques to screen women for precancerous conditions and treat abnormal tissue early. Among the most promising low cost and low-tech screening alternatives to the Pap smear, is visual screening, which only requires either simple vinegar or iodine solutions and the eye of a trained healthcare provider to spot abnormal tissue.
 
Screening linked to effective therapy
 
Increasingly, these simply tests are being linked with effective treatment. Increasingly, in LMIC relatively cheap and simple therapies are being used to either destroy or remove abnormal cervical tissue, depending on the severity, location and size of the affected area. Two such procedures include cryotherapy and loop electrosurgical excision procedure (LEEP). The former uses extremely low temperatures to destroy abnormal tissue and requires no electricity. The latter involves using a thin wire to remove lesions in the affected area. While this procedure requires more medical equipment than cryotherapy, it allows tissue to be removed for analysis, reducing the possibility that advanced cancer will go unnoticed. Although many LMIC have had cervical cancer prevention programs and simple treatment strategies in place for some time, some have failed to reduce death rates of the disease.
 
Radiotherapy and cervical cancer in LMIC
 
Research findings published in the May 2019 online edition of The Lancet Oncology suggest that the availability of radiotherapy in LMIC (where gross national income is <US$12,000 a year) would generate millions of productive life years and billions of dollars in economic benefits for the patients' families and communities. The study suggests that implementing a 20-year strategy for radiotherapy to treat cervical cancer in LMIC between 2015 and 2035, in parallel with an HPV vaccination program, would save the lives of some 9.4m women and provide a net benefit to economies of US$151.5bn as a direct result of women living longer and more productive lives.

According to Danielle Rodin, lead author and Radiation Oncologist at the Princess Margaret Cancer Centre, University of Toronto, Canada, "Vaccination is hugely important, but we can't neglect the millions of women who are contracting cervical cancer and dying in pain without access to treatment. These are women who have curable cancers: even advanced cervical cancer can be cured with radiotherapy. The possibility exists to make this treatment universally available". Radiation therapy makes small breaks in the DNA inside cells. This stops cancer cells from growing and dividing and causes them to die. Unlike cisplatin therapy, [an anti-cancer ("antineoplastic" or "cytotoxic") chemotherapy], which usually exposes the whole body to cancer-fighting drugs, radiation therapy is usually a local treatment.
 
According to the 2019 Lancet Oncology study, HPV vaccination would result in a 3.9% reduction in cervical cancer incidence over the 20-year study period; assuming a best-case scenario of vaccinating every 12-year-old girl in the world starting in 2014. By 2072, when the first vaccinated cohort reaches 70, there would be a 22.9% reduction in incidence, still leaving 41.6m in need for therapy over that time period.

“We know that when administered together (chemoradiation) you can give lower doses of both and get a better kill-rate on the tumour. This is now the backbone of cervical cancer therapy”, says Growdon; see video below.
 
 
Abu Dhabi’s endeavours to reduce cervical cancer
 
For some years, experts have discussed religious and cultural barriers to cervical cancer screening and drew attention to the relatively low levels of cervical cancer awareness and screening for women in Middle Eastern Arab countries. Meta-analysis of cervical cancer studies conducted in Arab countries between January 2002 and January 2017 and published in the December 2017 edition of Nursing & Health Sciences, suggest that in Arab speaking countries there tends to be, “low knowledge of and perceptions about cervical screening among Arab women, the majority of whom are Muslim. Factors affecting the uptake of cervical cancer screening practices were the absence of organized, systematic programs, low screening knowledge among women, healthcare professionals' attitudes toward screening, pain and embarrassment, stigma, and sociocultural beliefs”.
 
The success of HPV vaccination in Abu Dhabi and the UAE
 
Notwithstanding, there are signs that this is changing. Leading such changes is Abu Dhabi of the United Arab Emirates (UAE). Over a decade ago, a mandatory free HPV vaccination program for school girls was introduced by Abu Dhabi’s Ministry of Health and Prevention and extended in 2013 to include women between 18 and 26. Also, the Ministry recommends that woman aged 25 to 65 years get a Pap smear every three to five years. Since 2018, HPV vaccinations have been provided free and compulsory for all school girls in Dubai and the Northern Emirates following a campaign to raise awareness.
 
Although the UAE is among the few countries to have relatively low incidence rates of cervical cancer, the disease still ranks as the third most frequent cancer among women in the UAE and the third most frequent cancer among women between 15 and 44. Estimates suggest that every year, 93 women are diagnosed with cervical cancer and 28 die from the disease in the UAE. Although Abu Dhabi is successfully leading the fight against cervical cancer and provides a roadmap for others to follow, the incidence of cervical cancer in the Middle East generally is expected to more than double by 2035 (>33,000 cases) and be responsible for more than 18,000 deaths. In some countries including Morocco and Saudi Arabia, low societal awareness and relatively low levels of screening results in about one in four women with HPV.
 
 Takeaways
 
As cervical cancer screening and prevention programs have been growing and extending their reach, so increases the need to provide access to effective treatment. Despite growing awareness of the disease and global efforts to increase availability of appropriate resources, cervical cancer remains prevalent particularly in LMIC where effective treatment has not become widespread. In many LMIC, the default option is often to do nothing, which results in certain death. Researchers and policy makers should consider focusing their activities on how to best to reconcile the use of existing resources with the expected impact on the quantity and quality of life. Although gaps in oncological resources and barriers to treatment still exist, the good news is that there is increased political will and international attention to improve access to safe and effective treatment of cervical cancer. Notwithstanding, eradicating the disease globally appears to be more of a theoretical possibility than a medium term reality.
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6 years, 1 month ago

UK cancer care lags that of other European nations: reasons and solutions - Part 1

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  • International study shows that while British cancer survival has improved over the past 20 years the UK’s cancer survival rates lag behind the European average in 9 out of 10 cancers
  • 10,000 cancer deaths could be prevented each year if the UK hit the European average
  • Analysis shows that some British cancer survival rates trail that of developing nations such as Jordan, Puerto Rico, Algeria and Ecuador
  • Since the inception of the NHS in 1948 policy makers and clinicians have viewed the problem as the NHS being under staffed and underfunded
  • But the answers to the cancer care challenge in the UK are not that straight forward
  • The world has changed and is changing while policy responses to challenges have remained static
 
UK cancer care lags that of other European nations: reasons and solutions
Part 1
 
This Commentary is in 2 parts
Part 1 focusses on cancer care in the UK, but much of its substance is relevant to other advanced nations with aging populations and large and escalating incidence rates and costs of cancer. Before drilling down into cancer care in Britain we briefly describe the etiology of cancer, the epidemiology of the condition as it relates to the UK and other wealthy nations, mention immunotherapy as indicative of evolving and significant new therapies, which give hope to cancer sufferers. We then describe the CONCORD-3 study reported in The Lancet in 2018. This is a highly regarded and significant international study, whose findings are widely recognised as the “gold standard” of comparative cancer care. It reports that although 5-year cancer survival rates (the internationally accepted indicator of cancer care) have improved in Britain over the past 2 decades, the UK is still trailing that of most large European countries. We conclude Part 1 with a brief description of UK initiatives to close its cancer-gap with other European countries.
 
Part 2, which will be published in 2 weeks, is an analysis of the cancer-gap between Britain and other European countries. We suggest that for decades, healthcare providers, policy makers and leading clinicians have suggested that the UK cancer-care gap is because of the lack of funding and the lack of healthcare professionals. Since the inception of the NHS in 1948 a policy mantra of “more” has taken root among policy makers, providers and clinicians: predominantly, “more money”, “more staff”, and “the government should do more”. We suggest that, over the lifetime of NHS England, a combination of Britain’s economic growth, its historical ties with Commonwealth countries and, since 1973, the reduction of barriers to the flow of labour between European countries, has given UK policy makers a convenient “get-out-of-jail-card” because they could always provide more money and more staff. Over the past 2 decades, this option has become less and less effective because of a combination of the slowdown of world economic growth, the rise of emerging economies such as India, and more recently Brexit.
 
We conclude with some thoughts about why a significant cancer care gap has opened between the UK and other European nations, and briefly describe some UK initiatives to close the gap. We suggest that the world has changed quicker than the thinking of policy makers and quicker than structural changes in the UK’s healthcare system. Improving cancer care in the Britain will require more than inertia projects. It will require more innovation, more long-term planning, more courage from policy makers, more focus on actual patients’ needs rather than what we are simply able to provide. Since 1948, the healthcare baton in the UK has been with an establishment comprised of policy makers, providers and leading clinicians. Over the past 70 years this establishment has become increasingly entrenched in past and narrow policy solutions. It has failed because the world has changed while It has remained static. It is time that the healthcare baton is passed to people with less self-interest at stake, who are less wedded to the past, and understand the new and rapidly evolving global healthcare ecosystem.
 
The UK’s cancer challenge

While British policy makers and health providers appear keen to stress that trends in the 5-year cancer survival rates (the internationally accepted measure for progress against cancer) have improved over the past 20 years, there is an element of “economy with the truth” in what they say. The UK is being left behind by significant advances in cancer survival rates in other nations. Treatment for 3.7m UK cancer patients diagnosed since 2000 is struggling to progress, especially for people diagnosed with brain, stomach and blood cancers. Further, your chances of dying after being diagnosed with prostate, pancreatic and lung cancer in Britain is significantly higher than in any other large European nation. This is according to CONCORD-3, the largest ever international cancer study reported in the January 2018 edition of the The Lancet.
 
The emperor of all maladies
 
Cancer is the uncontrolled proliferation of cells. In his 2010 Pulitzer Prize winning book, ‘The Emperor of All Maladies’, Siddhartha Mukherjee, professor of oncology at Columbia University Medical School in New York describes cancer cells as, "bloated and grotesque, with a dilated nucleus and a thin rim of cytoplasm, the sign of a cell whose very soul has been co-opted to divide and to keep dividing with pathological, monomaniacal purpose." Cancer occurs when a cell starts to divide repeatedly, producing abnormal copies of itself, rather than dividing occasionally just to replace worn out cells. If the immune system fails to destroy these cells, they continue to reproduce and invade and destroy surrounding healthy tissue. A number of forces can trigger these cell divisions, such as certain chemicals (carcinogens), chronic inflammation, hormones, lack of exercise, obesity, radiation, smoking, and viruses. ‘The emperor of all maladies’ is not just one disease. There are over 200 different types of cancer, each with its own methods of diagnosis and treatment. Most cancers are named after the organ or type of cell in which they start: for example, cancer that begins in the breast is called breast cancer. Cancer sometimes begins in one part of the body and can spread to other parts of the body through the blood and lymph systems This process is known as metastasis.
 
A practitioners’ views

According to Whitfield Growdon, an oncological surgeon at the Massachusetts General Hospital and Professor of Obstetrics, Gynaecology and Reproductive Biology at the Harvard University Medical School, “Cancer is a complicated set of events, which can happen in any cell in your body. Your body is comprised of tiny cells, which have the ability to grow, stop growing and to re-model, which is necessary to do all the functions that are required for living. But every cell in nature has the potential to lose control of its growth. It is this uncontrolled growth of an individual cell, which we call cancer. Cells can grow, they can spread, and if the cell growth is uncontrolled it can invade other tissues, which can lead to you losing the ability to perform vital functions that are required for your life,” see video below:
 
 
Epidemiology

There is scarcely a family in the developed world unaffected by cancer. But, this has not always been the case. Cancer only became a leading cause of death when we began to live long enough to get it. In 1911, the prevalence of cancer was low compared to what it is today. Then life expectancy in the UK was 51.5 and 52.2 years for males and females respectively. Similarly, in the US, at the beginning of the 20th century, life expectancy at birth was 47.3 years. Today, the median life expectancy in the UK is 81.6 and in the US 78.7.  Significantly, the age at diagnosis for prostate cancer today is 67 and 61 for breast cancer. Approximately 12% of the UK population are aged 70 and above and account for 50.2% of the total cancers registered in 2014. 87% of all cancers in the US are diagnosed in people over 50.
Late diagnoses
 
Every 2 minutes in Britain someone is diagnosed with cancer, and almost 50% of these are diagnosed at a late stage. Every year in the UK there are more than 360,000 new cancer cases, which equates to nearly 990 newly diagnosed cancers every day. Taking a closer look at the UK data, we notice that since the early 1990s, incidence rates for all cancers combined have increased by 12%. The increase is larger in females than males. Over the past decade, incidence rates for all cancers combined have increased by 7%, with a larger increase in females: 8% as opposed to 3% in males. Over the next 2 decades, incidence rates for all cancers combined in Britain are projected to rise by 2%. Incidence rates in the UK are lower than in most European nations in males, but higher in females.

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Can AI reduce medical misdiagnosis?
 
 
Incidence rates of specific cancers in the UK

In 2015, breast, prostate, lung and bowel cancers together account for some 53% of all new cancer cases in the UK. Over the past decade, thyroid and liver cancers have shown the fastest increases in incidence in both males and females.  Incidence rates of melanoma, small intestine, and kidney cancers have also increased markedly in males over the past 10 years. Over the same period, Incidence rates of kidney, melanoma, and head and neck cancers have also increased markedly in females. Despite the rise in incidence rates, in recent years mortality rates from cancer in England and Wales have fallen. Between 1994 and 2013, mortality rates from cancer for males and females fell by 30% and 22% respectively.
 
New therapies: immunotherapy/biologics
 
What gives hope to people living with cancer is partly new and innovative therapies. Over the past few decades immunotherapy, also called biological therapy, is an evolving treatment, which has become a significant part of the management of certain cancers. Immunotherapy is any form of treatment that uses the body's natural abilities that constitute the immune system to fight infection and disease or to protect the body from some of the side effects of treatment. This may be achieved either by stimulating your own immune system to attack cancer cells specifically, or by giving your immune system components to boost your body’s immune system in a general way. Immunotherapy works better for some types of cancer than for others. It is used by itself for some cancers, but for others it seems to work better when used with other types of therapy.

According to Hani Gabra, Professor of Medical Oncology at Imperial College, London, and Chief Physician Scientist and Head of the Oncology Discovery Unit at AstraZeneca, UK, “Biological therapies are treatments gaining importance globally as we progress with the management of cancer. Understanding the biology of cancer has enabled us to understand the targets that go wrong in those cancers. We have successfully used many treatments that hit directly those cancer targets in order to inhibit or “switch-off” the cancers. These biological therapies either can be useful on their own or more commonly, combined with standard treatments such as chemotherapy, surgery and radiotherapy.” See video below:
 
 
Why is the CONCORD-3 study significant?

CONCORD-3 reported in a 2018 edition of The Lancet is an international scientific collaboration designed to monitor trends in the survival of cancer patients throughout the world, and involves 600 investigators in over 300 institutions in 71 countries. The study compares the overall effectiveness of health systems to provide care for 18 cancer types, which collectively represent 75% of all cancers diagnosed worldwide. The study is specifically designed to: (i) monitor trends in the survival rates of cancer patients world-wide to 2014, (ii) inform national and global policy on cancer control, and (iii) enable a comparative evaluation of the effectiveness of health systems in providing cancer care. The study is the third of its kind and supports the over-arching goal of the 2013 World Cancer Declaration, to achieve “major reductions in premature deaths from cancer, and improvements in quality of life and cancer survival”.
 
CONCORD’s evidence base
 
The evidence base of the CONCORD-3 study is significant and is predicated upon the clinical records of 37.5m patients diagnosed with cancer between 2000 and 2014. Data are provided in over 4,700 data sets by 322 population-based cancer registries from 71 countries and territories; 47 of which provided data with 100% population coverage. The analysis is centralised, based upon tight protocols and standardised quality controls, and employs cutting-edge methods. The 71 participating countries and territories are home to a combined population of 4.9bn (UN figures for 2014). This represents 67% of the world's population (7.3bn). The 322 participating cancer registries contributed data on all cancer patients diagnosed among their combined resident populations of almost 1bn people (989m), which is 20% of the combined population of those countries. CONCORD-3 contributes to the evidence base for global policy on cancer management and control.
 
CONCORD-3 data base drives national and global policies on cancer control

Despite the care taken of the data management processes, no study is perfect, and It is reasonable to assume that a study the size of CONCORD-3 will have weaknesses. Notwithstanding, the study is “best in class” and its results are comparable within the limits of data quality. The international trends in cancer patient survival reported in the study reflect the comparative effectiveness of health systems in managing cancer patients. The findings of CONCORD-3 form part of the evidence that drives national and international policies on cancer control. For example, the International Atomic Energy Agency use the findings in its campaign to highlight global inequalities in cancer survival. The Organisation for Economic Co-operation and Development (OEDC) use the results of CONCORD as indicators of the quality of healthcare in 48 countries in its Health at a Glance publications, and the European Union use the findings in its Country Health Profiles for EU Member States.
 
Overall cancer survival is improving

Overall findings of the CONCORD-3 study suggest that the prospects for cancer patients are improving throughout the world and survival rates are increasing for some lethal cancers. Several cancers show significant increases in 5-year survival, including breast (80% to 86%), prostate (82% to 89%), rectum (55% to 63%) and colon (52% to 60%); reflecting better cancer management. Notwithstanding, there are significant differences in cancer outcomes between nations.
 
UK has worse cancer survival rates compared with other European nations

Despite the fact that increasingly more people are surviving cancer, British adult cancer patients continue to have worse survival rates after 5 years compared to the European average in 9 out of 10 cancers. Research comparing 29 countries shows survival rates in Sweden are almost 33% higher than in the UK. For ovarian cancer, which affects 7,400 British women each year, the UK comes 45th out of 59, with only 36.2% sufferers surviving 5 years. Some countries achieve nearly double this survival rate. When the largest 5 European countries - Germany, France, Britain, Italy and Spain - were compared for the 3 most common cancers, Britain came bottom for 2 of them. Britain’s survival rates were worse than the other 4 European nations for lung and prostate cancer, and second worst for breast cancer. With regard to pancreatic cancer British patients had just a 6.8% chance of survival, compared to 7.7% in Spain, 8.6% in France, 9.2% in Italy and 10.7% in Germany. This puts the UK 47th out of the 56 countries that had full data for this cancer. Studies suggest 10,000 deaths could be prevented each year if the UK were to keep up with the European average. The UK only exceeds the European average in melanoma. See table below.
 
 
Takeaways

Here we have introduced and described the findings of CONCORD-3, which suggests the UK lags significantly other European nations with regard to cancer survival rates.  This sets the scene for part 2 of this Commentary, which will briefly describe some of the UK’s cancer initiatives to reduce premature death from cancer and enhance the care of people living with the disorder. Much has been achieved and over the past 2 decades, cancer mortality rates in the UK have been significantly reduced. Notwithstanding, more innovative and effective policies, which address the actual needs of patients rather than provide “more money and more staff” will be required if the UK is to reduce the cancer-care gap.
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6 years, 1 month ago

UK cancer care lags that of other European nations: reasons and solutions - Part 2

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  • International study shows that while British cancer survival has improved over the past 20 years the UK’s cancer survival rates lag behind the European average in 9 out of 10 cancers
  • 10,000 cancer deaths could be prevented each year if the UK hit the European average
  • Analysis shows that some British cancer survival rates trail that of developing nations such as Jordan, Puerto Rico, Algeria and Ecuador
  • Since the inception of the NHS in 1948 policy makers and clinicians have viewed the problem as the NHS being under staffed and underfunded
  • But the answers to the cancer care challenge in the UK is not straightforward
  • The global healthcare ecosystem has changed and is continuing to change faster than national policy responses
  • The UK’s cancer care challenges require more innovation not just more reports, more money and more staff
  
UK cancer care lags that of other European nations: reasons and solutions
Part 2

Part 1 of this Commentary  described the CONCORD-3 study reported in the January 2018 edition of The Lancet, which suggested that although 5-year cancer survival rates (the internationally accepted indicator of cancer care) have improved in Britain over the past 2 decades, the UK lags behind most large European countries in cancer care.
 
This is part 2 of the Commentary, which begins by describing some of the UK’s initiatives over the past 20 years to improve cancer mortality rates, speed up diagnoses and enhance the quality of cancer care for people living with the disease. All arrive at similar conclusions: that UK cancer care strategies have reduced cancer mortality rates over time, but there is still more that can be done. They do not compare Britain’s cancer mortality rates with other European nations. Notwithstanding, there appears to be some consensus among leading clinicians and policy makers that the UK’s failure to close the cancer care gap with other European nations is because NHS England is underfunded and understaffed. While this explanation might provide part of the answer it does not tell the whole story. The answer might be less to do with extra funds and extra staff, and more to do with the fact that the global healthcare ecosystem has changed quicker than the thinking of UK policy makers and quicker than structural changes to NHS England. To the extent that this is the case, improving cancer care in Britain may not require more money and more staff, but more innovation and more focus on actual patients’ needs rather than on what policy makers can provide politically.
 
National cancer initiatives: resolving patients’ needs or perpetuating the status quo?
 
Over the past 20 years the UK government has commissioned a number of strategies, taskforces and reports all aimed at improving cancer diagnoses, treatments, and management, and enhancing the quality of life of people living with the disease and reducing premature deaths. In 2000, NHS England launched a National Cancer Plan, which was, “committed to addressing health inequalities through setting new national and local targets for the reduction of smoking rates, the setting of new targets for the reduction of waiting times, the establishment of national standards for cancer services, and investment in specialist palliative care, the expansion and development of the cancer workforce, cancer facilities, and cancer research.” This was followed in 2007 by the Cancer Reform Strategy, which was designed to build, “on the progress made since the publication of the NHS Cancer Plan in 2000, and sets a clear direction for cancer services for the next five years. It shows how by 2012 our cancer services can and should become among the best in the world.”
 
Independent cancer taskforce
 
In January 2015, an Independent Cancer Taskforce was launched by NHS England, “to develop a five-year action plan for cancer services that will improve survival rates and save thousands of lives.” The NHS established the taskforce on behalf of the Care Quality Commission, Health Education England, Monitor,  Public Health England and theTrust Development Authority. The taskforce was chaired by Harpal Kumar, then, CEO of Cancer Research UK, and was comprised of representatives from a cross section of the cancer and healthcare communities.

In July 2015, the Independent Cancer Taskforce published a report entitled: Achieving world-class cancer outcomes: a strategy for England 2015-2020. The report identified key elements of a world class cancer care system and suggested that this is what British cancer patients should expect and what NHS England should aim to provide by 2020. The strategy included, “effective prevention (so that people do not get cancer at all if possible); prompt and accurate diagnosis; informed choice and convenient care; access to the best effective treatments with minimal side effects; always knowing what is going on and why; holistic support; and the best possible quality of life, including at the end of life.” According to the report such a strategy would achieve world-class cancer outcomes and save 30,000 lives a year by 2020.
 
2nd National Cancer Strategy

Two months before the publication of the Taskforce’s report, in May 2015, the UK government launched a National Cancer Strategy. This was its second 5-year program to implement a world-class cancer strategy designed to increase the prevention of cancer, speed up its diagnosis, and improve the experience of people with the condition. It suggested that rapid progress had been made in a number of key and high-impact areas, and stated that, “if someone is diagnosed with cancer, they should be able to live for as long and as well as is possible, regardless of their background or where they live. They should be diagnosed early, so that the most effective treatments are available to them, and they should get the highest quality care and support from the moment cancer is suspected.”

Report of the National Cancer Transformational Board
 
In December 2016, a National Cancer Transformation Board, led by Cally Palmer, the Cancer Director for England, published a number of specific steps to improve cancer care, and reported that over the past decade, 5-year cancer survival rates in the UK have improved across all main cancers, and at the end of 2016, cancer survival rates in Britain were at a record high with 7,000 more people surviving cancer compared to 2013.
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Interim report of the 2nd National Cancer Strategy

In October 2017, NHS England published an interim report of its 2015 National Cancer Strategy, which suggested that, “Survival rates for cancer have never been higher, and overall patients report a very good experience of care. However, we know there is more we can do to ensure patients are diagnosed early and quickly and that early diagnosis has a major impact on survival. We also know that patients continue to experience variation in their access to care, and this needs to be addressed. Early diagnosis, fast diagnosis and equity of access to treatment and care are central to the ‘National Cancer Programme’ and the transformation of services we want to achieve by 2020-21.” According to an NHS spokesperson, “Figures show that cancer survival is now at an all-time high in England, as a result of better access to screening, funding for effective new treatments and diagnostics and continued action to reduce smoking.”
 
Why cancer mortality rates in Britain lag other European countries
 
“If you look at similar European countries the proportion of GDP (Gross Domestic Product) the UK has spent on health in the last 10 to 15 years is low and has increased less than the others,” says Michael Coleman, Professor of Epidemiology and Vital Statistics at the London School of Hygiene & Tropical Medicine and co-author of the international cancer study reported in the March 2018 edition of The Lancet. UK healthcare spending fell from 8.8% of GDP in 2009 - when it averaged 10.1% in leading European countries - to 7.3% in 2014-15. “This difference between the likes of Germany and France is likely to explain some of what we are seeing,” says Coleman and he also suggests that, “The number of medical specialists who deal with these diseases [cancer] tends to be low compared to other similar countries,” [Our emphasis]. Let us examine the relative European healthcare spends and levels of staffing in NHS England.
 
Comparative GDP spends on healthcare

The OECD’s November 2016 Health at a Glance report suggests that in 2013 (the latest year for which data have been published) the UK spent 8.5% of its GDP on public and private healthcare. And, a 2016 report from the King’s Fund, a charity, suggests that projected spending on NHS England as a proportion of the UK’s GDP in 2020-21 is 6.6%, just 0.3% above what it was in 2000.
 
Challenges comparing healthcare spends

Notwithstanding, linking cancer mortality rates to the proportion of GDP nations spend on healthcare is not straightforward. This is partly because of, (i) different nations have different sources of healthcare funding, and (ii) a person’s purchasing power is different in different countries. Fluctuations in relative national economic growth make such comparisons over time and between nations challenging. According to The Health Foundation, a higher percentage of UKhealthcare spending is publicly funded compared to other European countries. For example, “In 2012, publicly funded spending accounted for 84.0% of UK healthcare spending. This is the third highest level in the EU-15 (average: 76.5%).  In 2012, UK public spending on healthcare was slightly higher than the EU-15 average of 7.6% of GDP”. Between 2008 and 2012 the average annual change in healthcare spending per person was lower for the UK than most EU-15 countries, which was largely the result of Greece, Ireland and Portugal making significant cuts to their healthcare spending. The rising prevalence of cancer and other chronic long-term diseases, is a significant driver of increased healthcare costs. According to OEDC data, UK spend on chronic lifetime conditions is similar to the European average. However, the UK spends less than other European countries on pharmaceuticals and out-of-pocket payments. Further, on average, UK patients spend less time in hospital and generally use fewer resources (measured in terms of staff and beds).
 
A 2017 paper published by the Nuffield Trust suggests that, when taking into consideration different sources of healthcare funding and purchasing power parity, the UK’s healthcare spend actually might be keeping up with that of other European nations.
 
NHS “dangerously” understaffed

Let us now consider staffing. In 2017, The Royal College of Emergency Medicine reported that primary and emergency care doctors, which are crucial for the early diagnosis of cancer, were experiencing significant recruitment and retention challenges. According to 2018 figures, NHS England has nearly 100,000 jobs unfilled, which include 35,000 nursing posts and 10,000 doctor vacancies.  The total vacancies represent 1 in 12 of all NHS posts, which is enough to staff about 10 large hospitals. Further, the high number of unfilled NHS posts coincides with 0.25m more people visiting A&E in the first quarter of 2018 than in the equivalent period in 2016. According to Saffron Cordery, the director of policy and strategy for NHS Providers, “These figures show how the NHS has been pushed to the limit. Despite working at full stretch with around 100,000 vacancies and a real risk of staff burnout, and despite treating 6% more emergency patients, year on year in December (2017), trusts cannot close the gap between what they are being asked to deliver and the funding available”. A February 2018 finance report suggests that NHS England is heading for a £931m deficit in 2018 and is "dangerously" understaffed. This year-on-year deficit was revised to a projected £1.3bn shortfall, which is 88% worse than planned.
 
Reasons for shortages of health professionals

The NHS staffing challenges are aggravated by the fact that British trainee primary care doctors are dwindling, newly qualified doctors are moving abroad, and experienced doctors are retiring early. Over the lifetime of NHS England, the UK has trained significantly fewer healthcare professionals than it needed, and the supply of qualified young British people has consistently outstripped the number of places in medical schools and nurse training. According to data from the General Medical Council (GMC), between 2008 and 2014 an average of 2,852 certificates were issued annually to enable British doctors to work abroad. A 2015 British Medical Association (BMA) poll of 15,560 primary care doctors, found that 34% of respondents plan to retire early because of high stress levels, increasing workloads, and too little time with patients.  Further, it is estimated that 10% of doctors and 7% of nurses employed by NHS England are nationals of other European countries. The uncertainties of Brexit (a term for the potential departure of the UK from the EU) add to NHS’s recruitment and retention challenges of healthcare professionals. According to a 2017 Health Foundation Report, in 2016, more than 2,700 nurses left the NHS; an increase of 68% since 2014.
 
UK policy approach to healthcare shortages has not changed

Notwithstanding, NHS staff shortages are not new. In the 1960s, NHS hospitals in Britain introduced mass recruitment from Commonwealth countries, and this has influenced staffing policies ever since. Being able to recruit doctors and nurses from foreign countries provided NHS England with an “easy” solution to staff shortages. However, over the past 2 decades the global healthcare ecosystem has changed significantly, while UK healthcare staffing policies have not kept pace with the changes. Today, there is a substantial gap globally in the supply and demand of healthcare professionals. Countries such as India, which traditionally could be relied upon to provide healthcare professionals for NHS England, have changed and the pool of potential Indian recruits have shrunk. Over the past 2 decades, the Indian economy has improved and the nation has developed a number of world-class hospital groups such as Apollo, Fortis and Narayana Health, which offer internationally competitive terms and conditions to Indian doctors and nurses. Increasingly Indian hospitals retain more of the nation’s healthcare professionals, and indeed attract doctors working in the UK and the US to return. Further, NHS England has tended to be staffed on the basis of what successive governments can afford rather than what NHS patients’ actually need.
 
Challenges of planning healthcare needs

Although there is a significant shortage of healthcare professionals in NHS England, it is not altogether clear that, (i) significantly increasing the number of NHS health professionals in the short to medium term will be possible, and (ii) simply increasing staff numbers will improve cancer care. Over the past 2 decades, as technologies and demographics have changed, so the demands on cancer professionals have changed. It is not necessarily the case that the NHS has the right mix of staff with the right mix of skills to deal effectively with changing conditions.  Changing traditional roles rather than simply boosting numbers might contribute more to reducing cancer mortality rates and improving the quality of cancer care. Further, it seems reasonable to suggest that, with the aforementioned challenges, a greater proportion of the UK’s annual healthcare spend might be more effective were it directed at cancer prevention rather than “diagnosis and treatment”.
 
Preventing cancer
 
A substantial proportion of cancers can be prevented including cancers caused by tobacco use, heavy consumption of alcohol, and obesity. According to the World Cancer Research Fund about 20% of all cancers diagnosed in the developed world are caused by a combination of excess body weight, physical inactivity, excess alcohol consumption, poor nutrition, and tobacco use, and thus could be prevented. Certain cancers caused by infectious agents such as the human papilloma virus (HPV), hepatitis C, (HCV), and human immunodeficiency virus (HIV) can be prevented by human behavioural changes, vaccination or treatment of the infection. Further, many of the 5m skin cancer cases worldwide (16,000 in the UK), which are diagnosed annually could be prevented by protecting skin from excessive sun exposure and not using indoor tanning machines.
 
Cancer screening
 
Screening is known to reduce the mortality of cancers of the breast, colon, rectum, cervix, and lung. Screening can help colorectal and cervical cancers by allowing for the detection and removal of pre-cancerous lesions. Screening also provides an opportunity for detecting some cancers early when treatment is less expensive and more likely to be successful. Early diagnosis is an important factor in improving cancer outcomes. Currently, the UK offers 3 national screening programs for bowel, breast and cervical cancer. Notwithstanding, recent reports suggest that these programs are not being fully utilised. For example, in 2017 the percentage of women taking up invitations for breast cancer screening was at the lowest level in a decade, dropping to 71%. Over 1.2m women in the UK (25% of the eligible population) did not take up their invitation for cervical screening. Further, a heightened awareness of changes in certain parts of the body, such as the breast, skin, eyes and genitalia may also result in the early detection of cancer.
 
Reconciling bureaucracy with innovation
 
We have described how UK cancer strategies are determined from the top. Cancer care professionals conform to internationally accepted standard processes, which facilitate and reinforce control. ‘Control’ and ‘conformism’ are in the DNA of cancer healthcare professionals and provide the cultural norms of NHS cancer care programs. NHS managers ensure conformance to clinical procedures, medications, targets, budgets, and quality care standards. This describes a classic “bureaucracy”, which is the technology of control and conformism, and the 70-year old command and control structure of NHS England. While control, alignment, discipline and accountability are very important to cancer care programs, innovation is equally important. If NHS England’s cancer mortality rates are to be compatible with those of other European healthcare systems we will have to find a way to reconcile the benefits of bureaucracy - precision, consistency, and predictability - while making the architecture and culture of our cancer care programs more innovative and more compatible with the demands of rapidly evolving 21st century science and technology.
 
Takeaways

Cancer is a vexed and profoundly challenging disorder. As soon as you read about a breakthrough you have news that the cancer has outwitted the scientists, hence the name, “the emperor of all maladies”. Cancer care in the UK has improved, but still the majority of British cancer patients would faire significantly better in other European countries. When reflecting on the myriad of cancer strategies, reports, and taskforces over the past 2 decade you cannot help but think that NHS England suffers from an element of bureaucratic inertia: the inevitable tendency of the NHS to perpetuate its established procedures and modus operandi, even if they do not reduce cancer mortality rates to those experienced by other European nations. The UK policy debate to resolve this problem tends to be dominated by “more”: more money, more doctors, more nurses. Historically this has provided successive governments with a “get-out-of-jail-card” because circumstances meant that the NHS could always provide more. This is not the case today. The global healthcare ecosystem has changed quicker than UK cancer strategies and quicker than structural changes in the nation’s healthcare system. Improving cancer care in the UK will require more than inertia projects. It will require more innovation, more long-term planning, more courage from policy makers, more attention to actual patients’ needs rather than providing what is politically available. The UK healthcare establishment should be minded of Darwin who suggested that, “It is not the strongest of the species that survives, nor the most intelligent, but the one most responsive to change.”
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8 years, 2 months ago

Is cancer avoidable?

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  • Cancer results when stem cells divide and mutate uncontrollably
  • Whether this is predominantly the result of intrinsic or extrinsic factors is unclear
  • Some experts say 65% of cancers result from intrinsic factors and are unavoidable
  • Other experts say most cancers result from extrinsic factors and are avoidable
  • Cancer strategy should not hide behind ‘bad luck’
  • Resources need to be allocated more smartly to prevent cancer

Is cancer the result of bad luck and unavoidable, or is it self-inflicted and prevented by simple lifestyles choices? Two 2015 studies arrive at strikingly different conclusions.
 
One, carried out by researchers from the John Hopkins Kimmel Cancer Centre and published in January 2015 in the journal Science, suggests that two thirds of cancers result from bad luck. Another, carried out by researchers from the Stony Brook Cancer Centre in New York and published in December 2015 in the journal Nature rebuts the findings of the Science paper, and suggests that 70 to 90% of cancer risk is self-inflicted and therefore can be avoided.

Which is right? And, why should this concern us?
 

Cancer

Cancer is a complex group of diseases characterised by the uncontrolled growth and spread of abnormal cells. If this is not checked it can cause death. Nearly 80% of all cancer diagnoses are in people aged 55 or older. Some facts about cancer In 2015 around 1.7m new cancer cases were diagnosed in the US, and about 330,000 in the UK. Each year, there are some 589,430 cancer deaths in the US, and some 162,000 in the UK. The annual treatment cost of cancer for the US is about $90bn and for the UK about £10bn. The causes of cancer include genetic, and lifestyle factors; certain types of infections; and environmental exposures to different types of chemicals and radiation.  Whitfield Growdon, Oncology Surgeon at Massachusetts General Hospital and professor at the Harvard University Medical School describes cancer and the causes of cancer.


         



         
           

 

The Science paper: cancer is unavoidable

The Science paper found that 65% of cancer cases are a result of bad luck: random DNA mutations in tissue cells during the ordinary process of stem cell division; regardless of lifestyle and hereditary factors. The remaining 35% of cancer cases, say the authors, are caused by a combination of similar mutations and some environmental and hereditary factors. One implication of these findings is that preventative strategies will not make a significant difference to the incidence rates of most adult cancers. So accordingly, the optimal way to reduce adult cancers is early detection when they are still curable by surgery.
 
Stem cell division is the normal process of cell renewal, but the extent to which random cell mutations contribute to cancer incidence, compared with hereditary or environmental factors, is not altogether clear. This is what the John Hopkins researchers sought to address with their study. Scientists examined 31 tissue types to discover whether the sheer number of cell divisions increases the number of DNA mutations, and therefore make a given tissue more prone to become cancerous.
 
Researchers developed a mathematical model, which suggested that it is incorrect to assume that cancer may be prevented with “good genes” even though we smoke, drink heavily, and carry excess weight. Their study found that, "the majority [of adult cancer risk] is due to bad luck, that is, random mutations arising during DNA replication in normal, noncancerous stem cells."  And, "this is important not only for understanding the disease, but also for designing strategies to limit the mortality it causes," say the researchers.
 
According to the Science paper bad luck mutations account for 22 of 31 adult cancer types, including ovarian, pancreatic, bone and testicular cancers. The remaining nine, including lung, skin and colorectal cancers, occurred more often than the random mutation rate predicted. This suggests that in these cancers, either inherited genes or environmental factors have a significant influence on cases.
 
“Our study shows, in general, that a change in the number of stem cell divisions in a tissue type is highly correlated with a change in the incidence of cancer in that same tissue,” says Bert Vogelstein, Clayton Professor of Oncology at the John Hopkins University School of Medicine, and co-author of the study. One example, he says, is in colon tissue, which in humans, undergoes four times more stem cell divisions than small intestine tissue. Likewise, colon cancer is much more prevalent than small intestinal cancer.
 
In a BBC Radio 4 interview Cristian Tomasetti, co-author of the study said: “Let’s say my parents smoked all their lives, and they never got lung cancer. If I strongly believed cancer was only environment, or the genes that are inherited, then since my parents didn’t get cancer, I may think I must have good genes, and it would be OK to for me to smoke. On the contrary, our study says ‘no’, my parents were just extremely lucky, and played a very dangerous game.”


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The Nature paper: cancer is avoidable

In a BBC interview, Yusuf Hannun, Director of the Stony Brook Cancer Center, Joel Strum Kenny Professor of Cancer Research and one of the authors of the Nature paper, challenged the findings of the ‘bad luck’ study. He suggests that hiding behind ‘bad luck’ is like playing Russian roulette with one bullet; one in six will get cancer. "What a smoker does is add two or three more bullets to the revolver and pulls the trigger. Although there is still an element of luck, because not every smoker gets cancer, they have stacked the odds against themselves. From a public health point of view, we want to remove as many bullets as possible from the revolver," says Hannun.
 
The Nature paper rebuts the John Hopkins ‘bad luck’ thesis. Its lead author, Song Wu, from the Department of Applied Mathematics and Statistics at Stony Brook University, notes that the Science paper had not conducted an alternative analysis to determine the extent to which external risk factors contribute to cancer development, and it assumes that the two variables: intrinsic stem-cell division rates, and extrinsic factors, are independent. “But what if environmental factors affect stem-cell division rates, as radiation is known to do?” asks Wu.
 
Wu and his colleagues provide an alternative analysis by applying four analytical approaches to the data that were used in the earlier Science paper and arrive at a radically different conclusion: that 70 to 90% of adult cancer cases result from environmental and lifestyle factors, such as smoking, drinking alcohol, sun exposure and air pollution. Wu admits that some rare cancers can result from genetic mutations, but suggest that incidence rates of cancers are far too high to be explained primarily by mutations in cell division.
 
According to the Nature paper, if intrinsic risk factors did play a key role in cancer development, the total number of divisions in tissue stem cells would correlate with lifetime cancer risk, and the incidence rates of the disease would be less than it actually is. Wu and his colleagues analyzed the same 31 cancer types as in the earlier Science paper, and evaluated the number of stem cell divisions in each. They then compared these rates with lifetime cancer incidence among the same cancer types. This allowed them to calculate the contribution of stem cell division to cancer risk.
 
Wu et al also pursued epidemiological evidence to further access the contribution of environmental factors to cancer risk. They analyzed previous cancer studies, which show how immigrants moving from regions of low cancer incidence to regions with high cancer incidence soon develop the same tumor rates, suggesting that the risks are environmental rather than biological or genetic.
 
The researchers’ findings suggest that mutations during cell division rarely accumulate to the point of producing cancer, even in tissues with relatively high rates of cell division. In almost all cases, the Nature paper found that some exposure to carcinogens or other environmental factors would be needed to trigger disease, which again suggested that the risks of the most prevalent adult cancers are due to environmental factors. For example, 75% of the risk of colorectal cancer is due to diet, 86% per cent of the risk of skin cancer is due to sun exposure, and 75% of the risk of developing head and neck cancers is due to tobacco and alcohol.
 
The Nature paper concludes that bad luck, or intrinsic factors, only explain 10 to 30% of cancer cases, while 70 to 90% of adult cancer cases result from environmental and lifestyle factors. "Irrespective of whether a subpopulation or all dividing cells contribute to cancer, these results indicate that intrinsic factors do not play a major causal role," say the authors. This suggests that many adult cancers may be more preventable than previously thought. 
 

Preventing cancer 

Even the Science study concedes that extrinsic factors play a role in 35% of the most common adult cancers, including lung, skin and colorectal cancers. This, together with the Nature study, and the rising incidence of avoidable cancers, should be a wake-up call because a substantial proportion of cancers can be prevented.
 
Hannun is right! Whatever the causes of cancer, we should not ‘hide behind bad luck’.  We should act on evidence, which suggests that it is within everyone’s capabilities to make simple lifestyle changes that can prevent common adult cancers.  Although maintaining a healthy lifestyle is no guarantee of not getting cancer, the Nature paper underlines the fact that a healthy lifestyle stacks the odds in your favor.  The paper supports preventative cancer strategies.
 
In 2015, tobacco smoking caused about 171,000 of the estimated 589,430 cancer deaths in the US. The Nature paper suggests that the overwhelming majority of these could have been prevented. In addition, the World Cancer Research Fund has estimated that up to 33% of the cancer cases that occur in developed countries are related to being overweight or to obesity, physical inactivity, and/or poor nutrition, and thus could also be prevented.
 
It seems reasonable to suggest that the risk of cancer can be significantly reduced by: (i) a cessation of smoking, (ii) drinking less alcohol, (iii) protecting your skin from the sun, (iv) eating healthily, (v) maintaining a healthy weight, and (vi) exercising regularly.
 

The UK Position

Everyone understands the enormity of the burden of cancer, and what to do to reduce its risk. In the UK, as in other wealthy countries, there is no lack of money, no lack of resources, and no lack of expertise for cancer care. The annual spend on cancer diagnosis and treatment alone in the UK is about £10 billion. The UK also has a government appointed Cancer Czar charged with producing a national cancer plan to bring Britain's cancer survival rates up to those of European levels. Despite our understanding and all these resources, a 2014 study published in the Lancet suggests that cancer survival rates in the UK still lag more than 20 years behind many other European countries, and that people are dying needlessly.  Why is this?
 

Fear of preventative medicine 

Writing in The Times in January 2016, Sir Liam Donaldson, a former UK Chief Medical Officer, suggested that although preventative healthcare strategies are vital “to provide safe, high quality care without running out of money”, governments avoid helping the public to mitigate the risks of modern living, which can cause cancer, because of  “two primal political forces: the mortal dread of being labeled a ‘nanny state’, and a fear of removing people’s perceived pleasures.”
 
During Donaldson’s tenure between 1998 and 2010, the government rejected his recommendation for a minimum unit price for alcohol, and for the same reasons in 2014, the government rejected a tax on sugar recommended by Public Health England. Excess sugar increases the risk of cancer, heart disease and diabetes. According to Donaldson, without effective government action to lower the vast and escalating burden of cancer, and other chronic diseases, the NHS is unsustainable.
 
The missing link in preventative strategies is behavioral techniques that engage people who are at risk and help them change their behaviors. Such techniques have been demonstrated to be successful in both the UK and US. They explain how people behave, and encourage them to reduce unhelpful influences on their health, and change the way they think and act about important health-related issues such as diets, lifestyles, screenings and medication-management. See: Behavioral Science provides the key to reducing diabetes
 

Takeaway 

It is crucial that the UK government now embraces behavioral techniques to curb the curse of cancer.  Donaldson is right: if cancer, and other chronic diseases, which together consume the overwhelming percentage of healthcare expenditure, are not prevented the NHS will become unsustainable.
 
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9 years, 10 months ago

Cancer survival and patient-centered healthcare

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DNA testing
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misdiagnosis
 
Since the early 1970s, there's been significant progress in the survival rates of some cancers, in particular testicular, skin, breast, and prostate cancers where the 10-year survival rates in the UK have increased, on average from 46% to 86%.

However, the UK still lags comparable European countries in cancer survival, and for some cancers, particularly lung, esophagus, pancreas and brain, the 10-year survival rates are only about 10% or less.

Late diagnosis
In Britain 50% of cancer patients are diagnosed late. This is the result of GPs misdiagnosing, and patient's reluctance to visit their doctors.

In his book, Malignant, Stanford University professor S Lochlann Jain suggests cancer diagnosis is missed in young adults because, "doctors often work under the misguided assumption that cancer is a disease of older people." For example, 80% of lung cancers are diagnosed at advanced stages.

Cancer survival rates are expected to improve as technology, and self-education develop. This is expected to reduce the role of primary care doctors, increase patient-centered healthcare, and reduce late diagnosis.
 
British stiff-upper-lip
In emerging countries, cancer patients present late because of a lack of education and money. In the UK, where medicine is free at the point of care, the British stiff-upper-lip is often the cause of late diagnosis.
 
A 2013 comparative study published in the British Journal of Cancer found that there was little difference in the awareness of cancer symptoms among patients, yet the British were less likely to act on them. It concluded that the traditional British 'stiff-upper-lip' means cancer patients are dying unnecessarily because they don't want to waste their GP's time with their symptoms or are too embarrassed to seek help.

 

Genomic medicine
A number of studies suggest that doctor-patient relationships are sub-optimal and based on asymmetry of information.
 
Such relationships will change when patients have access to information on their own DNA. Genomic medicine is a game-changer because of its potential to personalize patient care.
 
It only takes a few hours to sequence a person's genome, and costs are low and falling. A recent survey suggests that 81% of all US patients would like to have their genome sequenced. Eventually, this will mean that most people will have their genome sequenced so they can be properly cared for if they get sick.

Already some scientists and clinicians have started taking advantage of genomic sequencing, to tailor their approaches to individual differences.  In this personalized, patient-centred healthcare environment, primary care doctors are less important, and patients more important.  As this transformation occurs, early cancer diagnosis and survival rates are expected to rise.    
Technology driven patient-centered health
Increasingly, patients are employing the expanding array of mHealth apps to diagnose and treat their own ailments and this will increase as the technology develops and prices fall.

For example, patients have started using mHealth apps to measure activity, and changes in their vital signs and bodily functions. Current devices clipped to a finger can measure heart rates, and blood oxygen levels and these data can be transmitted to smartphones. Increasingly consumers will use these tools rather than visit primary care clinics.

Takeaways
Technological developments, self-education, and consumers' increased access to their health records, will help to correct the imbalance in information that now exists between doctors and patients.

As this happens, cancers will be diagnosed earlier, primary care centres will disappear, hospitals will exist only for intensive care, and sick patients with long-term chronic illnesses will be monitored and managed remotely from home.
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10 years, 8 months ago

What is tamoxifen?

Robert Leonard
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Tags:
breast cancer
breast cancer treatment
cancer prevention
endometrial cancer
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12 years, 7 months ago

What cancers can a smear test detect?

Hani Gabra
Directory:
Cancer
Tags:
cancer prevention
cervical cancer
pap smear test

A smear test is a very important part of women’s general health. It is an extremely effective way for preventing cervical cancer, which is a difficult disease in people’s development. However, in spite of it being such an important test in women’s health, a smear test does not have the ability to detect any disease other than cervical cancer.

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