Originally published in May-June 2004 icon - We have repeatedly asked to interview the Chief Executive of Cancer Research UK for a more up to date picture, but have always been turned down.
Aiming To Control Cancer In The Future
Dr. Lesley Walker, Director of Cancer Information at Europe´s largest cancer charity, Cancer Research UK, reveals details of their research into cancer prevention and screening. CANCERactive reporter Melanie Hart asked the questions to see how widely this differed from the CANCERactive precautionary principle.
Q: Dr Walker, please can you outline what Cancer Research UK plans to do for cancer prevention in the UK this year and over the next five?
A: First and foremost we are a research organisation, supporting a broad programme of research into the prevention of cancer. This includes investigating its causes, identifying people and groups of people at high risk, understanding behaviour that can increase cancer risk, and discovering ways to empower people to take risk-reducing action.
Smoking causes nine out of 10 cases of lung cancer, and is a major risk factor for at least 11 other types of cancer. Overall, one third of cancer deaths in the UK are estimated to be the result of smoking.
Cancer Research UK is supporting a broad programme of research aimed at improving smoking cessation worldwide, as well as informing social policy. This work includes:
* Providing statistics on the number of people who smoke, their risk of cancer, and the extent to which risk is reduced on stopping smoking.
* Investigating the reasons why people start smoking.
* Identifying ways to help people stop.
* Looking at how the constituents of cigarette smoke cause cancer.
* Supporting initiatives such as no-smoking days and organisations such as ASH. (Action on Smoking and Health).
* Finding ways to counter the activities of tobacco companies.
* Lobbying the Government to introduce changes in tobacco related policies.
Up to a third of cancers may be attributable to diet
Obesity is the major cause of cancer in non-smokers and, overall, up to a third of cancers may be attributable to diet. Diet is complex and, despite many studies, there have been conflicting results about the foods that harm and those that protect. To address this, Cancer Research UK is providing core support for the two UK arms of the largest study of diet and health ever undertaken. EPIC (European Prospective Investigation into Cancer and Nutrition) is a study of more than 500,000 people in 10 European countries. EPIC will investigate the relationship between diet, metabolic and genetic factors, and cancer. The variation in diet across Europe is very large, and this will increase the power of the study beyond that of some of the big American studies - where diet has been much more homogeneous.
The results of EPIC could have huge implications for cancer prevention. Initial analyses will focus on the common cancers - breast, lung, colorectal, prostate and stomach cancer - which collectively account for more than 140,000 cases of cancer every year in the UK. However, the size of the study means that researchers will also be able to investigate the role of dietary factors in rarer cancers. The results will be presented at international conferences, and published in journals available to researchers and health officials throughout the world.
Cancer Research UK also funds trials of treatments (chemoprevention) that may help to prevent cancer, and research to improve screening. In some cases screening can detect premalignant lesions and prevent cancer (for example cervical screening). Other screening methods aim to detect cancer early and to reduce deaths from the disease (known as secondary prevention), for example breast screening. In addition to the IBIS II trial of anastrozole in prevention of breast cancer in woman at increased risk, we are supporting chemoprevention trials to evaluate the role of aspirin and/or folate supplementation in the chemoprevention of polyps and bowel cancer. And recently, researchers launched a trial to see if it is possible to reduce the risk of oesophageal cancer developing in people with Barrett´s oesophagus. The trial will test if high or low dose esomeprazole (a proton pump inhibitor that reduces stomach acid) alone, or esomeprazole and aspirin together can help stop Barrett´s oesophagus developing into oesophageal cancer.
A diet high in salted and preserved foods and infection of the lining of the stomach are the main causes of stomach cancer
The charity is also involved in the development of vaccines against cancer, for example against the human papillomavirus (HPV) - the major causative agent of cervical, penile and vulval cancer. It is estimated that up to 20 per cent of all cancers worldwide are caused by chronic infection with certain viruses and bacteria. These cancers could be prevented either by vaccination or by early detection and treatment of infection. A diet high in salted and preserved foods, and infection of the lining of the stomach, by the bacterium helicobacter pylon, are the main causes of stomach cancer. We are supporting a trial to find out if stomach cancer can be prevented by screening healthy people for H pylon and treating those who are infected with antibiotics.
Our Cancer Information Department co-ordinates the UK´s national skin cancer prevention campaign, SunSmart. It is funded by the UK health departments and this year´s campaign will focus on children and young people, and will encourage parents to be SunSmart. One of the most vulnerable groups are young people travelling abroad for the first time. Our research has shown that there is still a worrying gap between how much people know about skin cancer and how little they actually do to protect themselves. A survey commissioned for the SunSmart campaign found that 75 per cent of the 1,850 people questioned are concerned that exposure to the sun can result in skin cancer. But less than 30 per cent use shade, and less than 40 per cent bother to apply high factor sunscreen, despite the fact that more than 65,000 cases of skin cancer are diagnosed in the UK each year.
Q:Last September, you said that developments in detecting four of the most feared cancers will see death rates fall in under a decade. Can you expand on this?
A: Early detection, improved treatments and effective prevention programmes will contribute to the vision of bringing cancer under control in the UK within two generations. Key to achieving this goal will be improvements in screening for breast and cervical cancer, the introduction of a screening programme for bowel cancer, and research on the early detection of prostate cancer.
We expect a continued decline in deaths from breast cancer, with an extra 600 lives saved each year in England and Wales, as the national screening programme extends its scope to women up to the age of 70.
We expect an extra 600 lives saved each year in England and Wales
Cervical screening has successfully reduced the numbers of cases from more than 4,500 each year, in the late 80s, to less than 3,000 cases a year now. The number of women affected is expected to drop further thanks to new techniques such as liquid-based cytology. This is being introduced across the country, in the first instance, to improve the quality of screening, but it will pave the way for automated screening in the future. Research on screening for HPV and for other cancer-specific markers is in progress and should lead to improvements in the specificity and detection rates of screening.
One of the biggest contributions to controlling cancer will come from developments in screening for bowel cancer. Cancer Research UK scientists have played a major role in providing the Government with evidence on the effectiveness of bowel cancer screening. national screening programme is likely to be introduced within the next five years, when evidence is available to support the choice of the most effective method. If flexible sigmoidoscopy is introduced, it could prevent some 5,000 cases each year in the UK. If faecal occult blood testing is adopted it could lead to a substantial reduction in deaths from the disease. For more details on both of these log on to: http://www.cancerhelp.org.uk/help/default.asp?page=2816.
Over the next decade, further research into prostate cancer detection and treatment will provide important answers on how best to manage the disease, the second biggest cause of cancer death in UK men. Cancer Research UK is investing in studies on prevention, detection and treatment of prostate cancer, including a new trial looking into the benefits of screening. We are optimistic that research on the gene alterations in prostate cancer will lead to more precise ways of determining who does and doesn´t need radical treatment (surgery or radiotherapy).
A national screening programme is likely to be introduced within the next five years
Other research is in progress. For example, Cancer Research UK is helping to support a major trial co-ordinated by researchers based at St Bart´s Hospital, in London, to see if blood tests or ultrasound screening for ovarian cancer improve early detection and survival from the disease. If these screening methods are found to be effective, the trial could lead to a national ovarian cancer screening programme.
Q:Can you outline the "improvements in screening for breast cancer" you mentioned? Are these the way mammography images are taken?
A: Women are now being screened up to age 70. We are also running a trial, with the Medical Research Council, to examine the potential benefits of extending breast cancer screening to women under the age of 50. Research is in progress to improve the quality and read-out of mammography images and to develop better screening methods. When women go for screening now, two scans are taken - one from above and one from the side. This is to make doubly sure that nothing is missed. However, we still need to find more effective ways of screening for breast cancer and considerable research is in progress, globally, using different methods.
Q:What are the new screening methods to detect early-stage disease you have mentioned (if different from the above) and when will they be introduced and for whom?
A: Decisions on the introduction of screening, and for whom, are made by the DoH. Researchers are working on tests for molecules that are involved in the cancer process - such as proteins involved in the duplication of DNA before a cell divides in two. For example, a simple urine test may potentially be used to diagnose bladder cancer. Researchers, funded by the charity, have discovered that high levels of a particular protein, McmS, in urine are linked to the presence of tumours in the bladder. This is now being investigated further in a clinical trial.
Q: You have underwritten up to lmillion for a new trial looking into prostate cancer screening, how long will this trial last?
A: The study will extend an existing trial called ProtecT (Prostate testing for cancer Treatment), funded by the NHS Health Technology Assessment programme, launched in 2001 to find the best treatment for early prostate cancer.
During 2001 to 2006, 120,000 men aged between 50 and 69 are being invited for a PSA
During 2001 to 2006, 120,000 men aged between 50 and 69, from 400 general practices in nine centres in the UK, are being invited for a PSA (Prostate Specific Antigen) test. Those with raised levels of PSA, who are found to have prostate cancer, are being treated with radiotherapy or surgery, or have no treatment but are actively monitored.
The extension to the trial, currently funded by Cancer Research UK and the Department of Health, will recruit another 400 general practices from the nine centres across the UK. Data will be collected on prostate cancer patients from these practices. Researchers will then compare the death rate in men invited for screening in the ProtecT trial with those not invited for screening. The data gathered will allow for a detailed investigation of the impact of early diagnosis and treatment, and the benefits that future population screening for prostate cancer could achieve.
There are few international issues in health care as controversial as prostate cancer screening. But the high quality research needed to answer the debate has been lacking until now. The new trial will finally reveal whether screening the population for prostate cancer can save lives, and if the benefits of screening out-weigh the costs.
Q:We´re all in favour of screening at icon, but how are you going to remove the dangers (for example:regarding brain tumours, recent Swedish research has shown that young people who have just one X-ray on their head before the age of 12 end up with lower IQs), and how are you going to get around the concern that actually mammograms and PSA tests over diagnose?
A: We are not proposing to screen children for cancer. Cancer is uncommon in young people and screening would be inappropriate. At the population level, the benefits of mammography outweigh the disadvantages, with an increasing number of malignant breast tumours detected at an early stage. However, the screening programme does pick up a significant number of cases of ductal carcinoma in situ (DCIS), and critics of the breast screening programme have voiced concerns that identifying DCIS is over diagnosis of breast cancer, as these lesions may never progress or threaten a woman´s life. But the majority of DCIS detected by screening are high grade or necrotic lesions, and there is convincing evidence that detection of DCIS and subsequent treatment prevents the development of high grade invasive cancer with a poor prognosis.
We do not recommend population screening for prostate cancer using the PSA test
We do not recommend population screening for prostate cancer using the PSA test. Only a quarter to a third of asymptomatic men with abnormally high PSA levels will have prostate cancer, so many men who do not have the disease would suffer anxiety and the risk of follow-up investigations. PSA is a useful test for men who have possible symptoms of prostate cancer but up to 20% of men with prostate cancer have normal PSA levels. Also the natural history of the disease is poorly understood. As a result it is not always possible to predict which tumours need treatment, and which need little or none. Some patients will therefore receive unnecessary treatment, some of it with appreciable side-effects. Finally, there is little evidence currently that PSA screening reduces death rates from prostate cancer. Population screening trials to detect early treatable disease are in progress (see above) and research is underway to detect biological or genetic markers that can identify aggressive tumours which require intensive treatment.
Q:Can you explain what liquid-based cytology (Q2) is and how it improves the quality of cervical cancer screening. Is this currently available all around the UK?
A: The NHS screening programme is introducing a new way of preserving the cells taken in smear tests. It is called liquid based cytology (LBC). The nurse collects the cells from the cervix in the same way, but using a very small brush instead of a spatula. The head of the brush is broken off directly into a small pot of liquid, instead of putting the cells straight onto a slide. This is better at preserving the cervical cells, and so the results of the smear test are more reliable. At the moment, about one in 12 PAP smears have to be done again because they can´t be read properly. This causes a lot of anxiety for women. With LBC, far fewer smears will have to be repeated.
There are three pilot hospitals already using LBC in England, in Bristol, Newcastle and Norwich. LBC will be rolled out nationally across the cervical screening programme. See: http://www.cancerscreening.nhs.uklcervical/lbc.html#implemented
Q:Is Cancer Research UK sponsoring research into vitamin alternatives to drug therapies (such as the research project for which Dr Bali Rooprai is trying to raise 200,000, to investigate the effect of a range of micronutnients - including selenium, red clover isoflavones and chokeberry - on malignant brain tumours)?
A: Cancer Research UK has already funded a pilot study of selenium supplementation in cancer prevention, but we have not succeeded in finding the necessary funding partners for a major study. We know that many people are interested in complementary medicine
, and the National Cancer Research Institute (the NCRI, a virtual institute comprising the major funders of UK cancer research) has agreed to encourage and develop research on complementary treatment.
Cancer Research UK is open to receiving applications for funding for research on complementary therapies
Cancer Research UK is open to receiving applications for funding for research on complementary therapies but these will be judged by the same rigorous criteria as all other applications for research on treatment and prevention. European legislation, which will come into force in the near future will impose the most rigorous standards yet for therapeutic clinical trials.
Q: What are your plans for prevention in schools?
A: Cancer Research UK´s primary role is to fund research. Over the years we have funded many projects in schools, on the development of teaching programmes, to help young people say no to smoking, and to support schools in the development of sun protection policies and resources for teaching about the dangers of over-exposure to the sun and how to avoid it. There is an element within this year´s SunSmart campaign that is focused on schools. There are more details on:http://www.cancerresearchuk.org/sunsmart/kidsandthesun/
We are supporting a study of the health and behaviour of teenagers, known as HABITS. In 1999, more than 4,000 pupils, aged 11 tol2, were recruited from 36 secondary schools in inner and outer London. They have been followed up annually by researchers. The study aims to collect data on the health behaviours adopted during adolescence that influence adult cancer risk, to find out how this varies with age and across diverse backgrounds. The ultimate aim is to develop and target health promotion in schools when it will achieve the maximum impact.
Q:Are there any plans to change hospital meals in cancer wards?
A: We are not responsible for them. You´ll have to discuss this with the NHS/DoH. However, we do think that hospitals and schools should lead the way in providing healthy meals.
Q: Are you planning campaigns to talk about prevention?
A: Cancer Research UK develops and distributes hundreds of thousands of leaflets about cancer every year to increase awareness and provide evidence-based information about risk factors, strategies for reducing the risk and the early signs and symptoms of cancer. The leaflets are available through the charity´s shops, on our website, or by sending a SAE to Cancer Research UK. The charity also runs the Cancerhelp UK site: (www.cancerhelp.org.uk
) to offer advice to people on every aspect of cancer. There is also a team of cancer nurses who operate Cancer Research UK´s nurse helpline.
Q:What is Cancer Research UK´s position on HRT and breast cancer?
It would be sensible to take HRT for only as long as necessary
A: It would be sensible to take HRT for only as long as necessary to deal with a particular medical problem. We advise women to discuss the options with their doctor, as it is not possible to generalise.
Some kinds of hormone replacement therapy (HRT) have a much greater effect on a woman´s risk of breast cancer than others. The Million Women Study, funded by Cancer Research UK, the NHS Breast Screening Programme and the Medical Research Council, confirmed that current, and recent, use of HRT increases a woman´s chance of developing breast cancer, and that the risk goes up with longer duration of use.
Current users of all types of HRT, including oestrogen-only, combined oestrogen-progestagen and tibolone, are at increased risk of breast cancer compared with women who have never used HRT. But the risk is substantially greater for users of combined preparations than for women on the other types.
Scientists at Oxford´s Cancer Research UK Epidemiology Unit analysed data from more than a million women between, the ages of 50 and 64. Women joined the study between 1996 and 2001, and half were using HRT or had done so in the past.
The study included 9,364 cases of invasive breast cancer and 637 breast cancer deaths, registered over 2.6 and 4.1 years of follow-up respectively.
Researchers found thatpost-menopausal women, using combination HRT, were twice as likely to develop breast cancer as non users (a 100 per cent increase), while risk increased by 45 per cent among users of tibolone and by 30 per cent among users of oestrogen-only HRT. These effects were shown to wear off within a few years of ceasing use.
Post-menopausal women, using combination HRT, were twice as likely to develop breast cancer as non users
In developed countries, among 1,000 postmenopausal women, who do not use HRT, there will be about 20 breast cancer cases between the ages of 50 and 60. For every thousand postmenopausal women who begin 10 years of HRT use at age 50, there will be five extra cases of breast cancer among users of oestrogen-only HRT and 19 among users of oestrogen-progestagen combinations.
So combined HRT causes four times as many extra breast cancers as oestrogen-only.
We estimate that over the past decade, use of HRT by UK women aged 50-64 has resulted in an extra 20,000 breast cancers, oestrogen-progestagen therapy accounting for 15,000 of these.
Combined oestrogen-progestagen HRT is usually prescribed for women who still have a uterus, to avoid the increased risk of cancer of the uterus caused by oestrogen-only therapy.
Since our results show a substantially greater increase in breast cancer with combined HRT, women need to weigh the increased risk of breast cancer caused by the addition of progestagen against the lowered risk of uterine cancer. Comparing the risks is by no means simple, and women may want to discuss options with their doctor.
Ed: As readers may know, CANCERactive´s approach to Cancer Prevention is very different. We advocate the Precautionary Principle - that where there is expert research expressing concern, we will tell you about it as it is your right to know, and to take the action you personally see fit.
We feel that Cancer Research take a very limited view on Cancer Prevention. There is little on their web site, for example, on toxic chemicals, pesticides, EMF´s and other factors which expert research has identified as possibly increasing the risk of cancer. To go to our home page on Cancer Prevention please click THIS LINK.