Certain cancers may be avoided and general health improved if you adopt a healthier lifestyle.

Any recommendation made to reduce cancer occurrence should not be one which could lead to an increased risk of other diseases. The recommendations which comprise the revised European Code Against Cancer should, if followed, also lead to improvements in other aspects of general health. It is also important to recognise from the outset that each individual has choices to make about their lifestyle some of which could lead to a reduction in their risk of developing cancer. These choices, and the rationale underlying their recommendation, are presented below.

European Code against Cancer and scientific justification: third version (2003)

Many aspects of general health can be improved, and certain cancers avoided, if you adopt a healthier lifestyle.

Do not smoke; if you smoke, stop doing so. If you fail to stop, do not smoke in the presence of non-smokersView
Avoid ObesityView
Undertake some brisk, physical activity every dayView
Increase your daily intake and variety of vegetables and fruits: eat at least five servings daily. Limit your intake of foods containing fats from animal sourcesView
If you drink alcohol, whether beer, wine or spirits, moderate your consumption to two drinks per day if you are a man and one drink per day if you are a womanView
Care must be taken to avoid excessive sun exposure. It is specifically important to protect children and adolescents. For individuals who have a tendency to burn in the sun active protective measures must be taken throughout lifeView
Apply strictly regulations aimed at preventing any exposure to known cancercausing substances. Follow all health and safety instructions on substances which may cause cancer. Follow advice of national radiation protection officesView

There are public health programmes that could prevent cancers developing or increase the probability that a cancer may be cured

Women from 25 years of age should participate in cervical screening.This should be within programmes with quality control procedures in compliance with European Guidelines for Quality Assurance in Cervical ScreeningView
Women from 50 years of age should participate in breast screening. This should be within programmes with quality control procedures in compliance with European Union Guidelines for Quality Assurance in Mammography ScreeningView
Men and women from 50 years of age should participate in colorectal screening. This should be within programmes with built-in quality assurance proceduresView
Participate in vaccination programmes against Hepatitis B Virus infectionView

 

Additional Items

Read About Various Screenings

 

 

:: Cellular telephones and cancer

The use of cellular phones and possible adverse health effects related to their use, attract much attention. Reports of brain tumour excesses occurring among phone users, case stories in the press and reports on thermal as well as magnetic effects on exposed tissue hypothesised to stimulate tumour growth, combined with the explosion in subscribers to cellular phones, raise public concern. The radiation from the cellular phones is characterised as non-ionising, alongside radar, microwave ovens and electrical wiring configuration. The radio frequency signals emitted from the devices range between 450 and 2200 MHz, i.e. in the microwave region of the electromagnetic spectrum. A comprehensive review of the epidemiological literature was recently carried out by Boice and McLaughlin [15] and published by the Swedish Radiation Protection Authority. They conclude, after a review of nine major studies (two cohort studies on cancer, three hospital based case–control studies, one incidence population based case–control study and two prevalence based case– control studies), that no significant association is present for brain tumours and use of cellular phones, irrespective of duration of use, type of phone (digital or analogue), tumour morphology or laterality. The follow-up, however, is short, and even if relative risks are unlikely to exceed 1.3 it is important to monitor this exposure to exclude the possibility of any long-term effects. On the other hand, no biological mechanism supports a causal relation and there is no evidence of adverse effects on laboratory animals.

:: Power lines and cancer

Power lines produce extremely low frequency (ELF) electromagnetic fields in range of 50 Hz to 60 Hz. Electric fields do not reach people inside houses, but magnetic fields go through most materials and cause an additional exposure higher than the typical background field (about 0.1 µT) up to a distance roughly 50 metres from the power line, depending on the voltage and wire configuration. Health effects on humans related to this non-ionising type of radiation have been investigated in epidemiological studies for over two decades.

The first report of an association between childhood cancer and power line exposure was published in 1979, and after that at least 24 studies on the same topic have been published. There have been two meta-analyses published lately that both suggest a significant 1.7–2.0-fold excess of childhood leukaemia in the extremely rarely existing fields above 0.3 or 0.4 µT. The excess may be attributable to patient selection and publication bias, and a plausible biological mechanism is not known.

It appears on the basis of studies with large numbers of cancer cases that there is no excess risk of cancer among adults living close to power lines, but the possibility of an association between some cancers and exposures to ELF magnetic fields is suggested by some occupational studies.

IARC classified ELF magnetic fields as possibly carcinogenic to humans (Group 2B) in its evaluation[14], while ELF electric fields were considered not to be classifiable as to their carcinogenicity to humans (Group 3). This evaluation only considers the likelihood of an association, but does not take into account the magnitude of the possible risk to individuals nor the population attributable risk. The results of epidemiological studies suggest that appreciable magnetic field effects, if any, are concentrated among relatively high and uncommon exposures.

:: Populations living near nuclear installations

Various studies have been carried out of cancer rates in the vicinity of nuclear installations in recent years, mostly in Western Europe and North America. Doses to populations around these installations were generally several orders of magnitude lower than those to persons living near the Techa River in Russia at the time of high discharges from the Mayak plant. There is evidence of raised cancer risks in this latter group, although quantification is difficult.

There does not appear to have been a general increase in rates of adult cancers around nuclear installations. Some, but not all, studies have indicated increased rates of childhood cancers and particularly childhood leukaemia. The evidence for such increases has tended to be strongest in the vicinity of nuclear reprocessing plants; in particular, Sellafield and Dounreay in the UK and, to a lesser extent, La Hague in France. Interpretation of these studies has been hindered in part by small numbers of cases and by the ecological (correlation) study design used in many instances. Assessments of radiation doses to those living near these installations do not suggest that the raised childhood leukaemia risks can be explained on the basis of radioactive discharges. Case–control studies generally do not demonstrate clear links with habits that might give rise to enhanced environmental exposures. A case– control study around Sellafield suggested a link between childhood leukaemia and paternal occupational radiation exposure prior to conception. However, this has not been replicated in larger studies elsewhere, and may have been a chance finding. Non-radiation factors such as population mixing have been mentioned as possible explanations for the raised risks, but it is unclear whether these factors could explain all the results.

At present, specific actions are not indicated over and above existing guidelines on radiation exposures to members of the public. However, continued monitoring of environmental radioactivity and cancer rates around nuclear installations is desirable.

:: Nuclear workers

Many studies have been carried out of cancer among nuclear industry workers. Most of the exposures to these workers were in line with international standards. In contrast, many workers at the Mayak plant in Russia received high doses over a protracted period, and raised (but poorly quantified) risks have been seen for several types of cancer in this group. Some of the worker studies have been limited by relatively small population sizes and/or short follow-up periods. The larger studies include a combined analysis of abaut 95.000 workers in Canada, the US and the UK, and cohorts of over 100.000 nuclear workers in Japan (although with a short follow-up) and the UK. Most of the analyses have looked only at mortality. There has been some variation in the findings, which may be due in part to low statistical precision. However, mortality has often been lower than in the general population, due probably to factors associated with selection into and continuation of employment. The larger studies have tended to indicate an increasing trend in leukaemia risk with increasing dose, whereas the evidence for a dose-related increase in solid tumour risks has generally been less. However, the confidence limits for these trend estimates have been relatively wide, and encompass risks extrapolated from the Japanese atomic-bomb survivors as well as a range of values, both higher and lower. More precise information will be obtained from an ongoing international collaborative study of cancer risk in nuclear industry workers.

At present, the findings from these studies do not indicate the need to modify current radiation protection measures for workers.

:: Radioiodine and thyroid cancer

Ionising radiation is the only definitely established cause of thyroid cancer in humans, although only a small proportion of thyroid cancers can be accounted for by radiation. The thyroid gland is highly susceptible to ionising radiation presumably because of its superficial location, high level of oxygenation, and high cell turnover rate. A pooled analysis of seven studies revealed that thyroid cancer was induced even by low doses of brief external gamma radiation in childhood, but rarely developed after exposure in adulthood. Data from the atomic bomb survivors underline the strong modifying effect of age at exposure, with no excess risk seen in individuals older than 20 years. During the first 14 years after the Chernobyl accident, approximately 1800 thyroid cancers were diagnosed in the three most contaminated countries among children younger than 15 years, whereas only three or four childhood thyroid cancers were registered annually in the same area before the accident. No increased thyroid cancer as a consequence of the Chernobyl accident has been identified in adults.

The major concern regarding medical use of ionising radiation has been the possibility that thyroid examinations or treatments using radioiodine cause thyroid cancer. The annual number of thyroid examinations using radioiodine is currently 5 per 1000 individuals in the western world. Patients treated with 131I for hyperthyroidism are almost entirely adults and no increased risk of thyroid cancer is seen among these patients. It is also likely that the doses, ranging from 100 to 300 Gy, received by the thyroid gland induce cell killing instead of carcinogenic transformation.

:: Cosmic radiation and cancer

Recently, several epidemiological studies have been carried out to investigate cancer mortality and cancer incidence among airline crew. Many exposure studies have been conducted to estimate and to measure the dose of cosmic radiation at flight altitudes of jet aircraft. The latter studies conclude that a typical annual radiation dose is between 3 and 6 mSv for a commercial pilot. Values up to 9 mSv have been estimated for a pilot flying some 600 h/year on polar flights at 10 km and above. Detailed assessment of individual flight history has showed that for all pilots the lifetime cumulative exposure was below 100 mSv. Results of the mortality studies and incidence studies are as yet inconclusive, although for most cohorts the total cancer (mortality and incidence) was not raised compared with the general population. For specific cancer sites, increased and decreased standardised mortality or incidence ratios were observed without a clear pattern. Leukaemia risk is not increased, with the exception of a study of Danish pilots, based on only 14 cases. A more consistent finding is an increased risk of breast cancer, which is also a cancer associated with radiation. The role of risk factors other than radiation, such as late first childbirth and low parity, may not always have been fully taken into account when evaluating these findings. Another consistent finding is an increase in skin cancer and melanoma. Whether this is related to leisure activities, occupational factors or a combination of both needs further investigation.

The overwhelming evidence does not point to a significant adverse health effect in terms of cancer, and the present regulation of aircrew as radiation workers sufficiently controls the occupational exposure. Very few passengers will ever accumulate radiation doses from cosmic radiation in the same magnitude as the staff and hence no particular precautions need to be taken.

:: Ionising and non-ionising radiation

Ionising radiation at high doses causes cancer in humans: only a few cancer types have never been related to ionising radiation. This has been known for decades, and excellent summaries of the scientific literature are available. The International Agency for Research on Cancer (IARC) recently classified X-rays, g-rays and neutrons as carcinogenic to humans (Group 1). This is irrespective of the different patterns of energy release and penetrating power of the different types of ionising radiation. Energy at high levels may lead to cellular and DNA damage followed by cell killing, whereas at lower doses it may lead to mutations increasing the risk of cancer. The International Commission on Radiological Protection (ICRP) issues recommendations for radiological protection based on the existing scientific literature.

High-dose ionising radiation is used in medicine to treat cancer. These types of exposures are at present outside the scope of the European Code Against Cancer. However, much of our evidence on the effects of ionising radiation on humans is derived from such uses, and from the atomic bomb survivors at Hiroshima and Nagasaki. The main source of radiation to the human population comes from the natural background, both terrestrial and cosmic, whilst the man-made sources, such as atmospheric nuclear testing, nuclear accidents (e.g. Chernobyl) and nuclear power production, which cause the most public concern, cause only very little exposure (Table 9).

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) estimates the population risk of dying from cancer after an acute dose of 1000 mSv is about 9% for men and 13% for women. The estimates could be reduced by 50% for chronic exposures. The worldwide average annual effective dose is 2.4 mSv. The lifetime exposure of the population to all sources of ionising radiation was estimated by the National Radiological Protection Board to account for 1% of all fatal cancers in the UK.(http://www.nrpb.org/radiationtopics/risks/cancer risk.htm – 22 November 2002). Only 1% of this risk is ascribed to the small doses from man-made radiation.

For the purpose of the European Code Against Cancer, this review concentrates on the possible effects of the natural background radiation, terrestrial (in the form of radon gas) and cosmic radiation, as it is possible to control exposure to both. Furthermore, we assess the cancer risk related to the Chernobyl accident and that among nuclear workers and people living near nuclear installations. Diagnostic radiation is of concern for the population groups undergoing examinations, be it screening of healthy individuals with mammography or computed tomography (CT) scans for lung cancer or when there is a suspicion of thyroid disease. Screening with low-dose CT for lung cancer is reported to give an effective dose of between 0.2 and 1 mSv. Using the risk factor of 5% per 1 Sv (ICRP 60), this would imply one to five radiation induced fatal cancers per 100.000 examinations. Mammography screening for breast cancer typically gives an absorbed average glandular dose of 3 mGy. It has been estimated in Sweden that among women aged 50–69 years, with a reduction in breast cancer mortality due to a mammographic screening programme of 25%, that 560 deaths from breast cancer would be avoided. It is estimated that the effect of the radiation would be to induce between 1 and 5 fatal breast cancers per 100.000 examinations. Although the collective dose from diagnostics to the population is small relative to natural radiation, benefit analyses should be performed to avoid unnecessary exposure.

Non-ionising radiation from sources such as power lines, electrical equipment, mobile phones and solar radiation raise public concern as to a possible carcinogenic effect. The ICNIRP (International Commission on Non-ionising Radiation Protection) issues guidelines for limiting exposure, and the German “Stralenschutzkommission” and the UK NRPB recently published reviews assessing the health risks. The evidence on power lines and mobile phones are dealt with in this section, whereas solar radiation is dealt with separately.