SCREENING

The National Health Service UK Breast Screening Programme was initiated in 1988. All women in Scotland aged 50 and over are entitled to free mammography screening from the National Health Service. Women aged 50 to 70 will automatically be called for screening – women over the age of 70 may request screening. Some women assume that as soon as they reach the age of 50, they will be called for screening. This is not the case. The Screening Programme operates over a three yearly cycle so some women will be approaching or just past their 53rd birthday before being called.

Whilst SBCC acknowledges the importance of the National Screening Programme and rigorously defends the right of all women to have access to screening, it is not within our remit to actively promote screening. Moreover, as an advocacy organisation dedicated to informing women on all issues of breast cancer, we are obliged to point out that there is great debate within medical circles regarding the efficacy of screening.

The controversy surrounding screening periodically surfaces, usually when a report is published – either for or against the benefits of screening. The debate can sometimes become quite complicated to follow, with detailed statistical analysis being used to prove or disprove a point. The following points are our brief guide to the debate – these are by no means exhaustive and SBCC is not expressing an opinion.

The argument in favour of screening the entire population:-

Screening increases the number of women being diagnosed with breast cancer. After the introduction of the National Screening Programme in 1988, breast cancer incidence increased significantly.

Screening, by picking up breast cancer at an early stage, can, in some instances, improve survival outcomes. Screening can pick up very small cancers before they have spread to the lymph nodes, and can even pick up pre-cancerous tissue.

The latest research undertaken by the NHS shows that the NHS Breast Screening Programme is now saving 1,400 lives every year in England.

The anxiety caused by a recall for further tests, which may then go on to prove that cancer is not present, is a small price to pay for the peace of mind which an all clear screening gives to most women.

The argument against screening the entire population:-

Screening does not prevent breast cancer.

The huge resources required to implement a national screening programme could be better deployed in primary prevention or targeted towards those women at higher risk.

Some cancers are missed at screening, producing a “false negative” outcome i.e. some women are falsely reassured that they do not have breast cancer.

Some women are recalled for further tests because of an abnormality, which later prove to be harmless, producing a “false positive” outcome i.e. some women undergo further invasive testing needlessly and are subjected to additional anxiety and worry whilst waiting for the results.

Some cancers (and pre-cancers) which are picked up at screening would have gone undetected in the lifetime of the woman i.e. the cancer would not have spread out with the breast during the woman’s life. The stress and traumatic life-changing effects of breast cancer surgery and treatment will be endured needlessly.

X-ray exposure increases the risk of cancer; screening is an x-ray. As yet, there are no statistics available which can determine how many breast cancers are caused by screening.

The actual number of lives saved by a National Screening Programme is debatable. Breast cancer survival rates have increased significantly over the past 20 years but statisticians and researchers find it difficult to determine how much of this is due to screening and how much to improved treatment regimes.

In view of the conflicting evidence, our advice on screening is to

“BE INFORMED”.

For pro-screening advice log onto www.cancerscreening.nhs.uk where there are references to various papers supporting a national breast screening programme, most importantly “The Forest Report” on which the UK national screening programme was based. Alternatively, discuss the issue with a breast care nurse at your screening centre when you are called for screening.

Information disputing the positive effects of screening is more difficult to access – not because this information does not exist, but because present government policy is to promote the screening programme and therefore it is not appropriate for this type of information to be included on a government-funded website.

One of the best organisations for producing access to unbiased and comprehensive reports is The Cochrane Library which can be accessed at www.cochrane.org. In the following extract, the Cochrane Library has reviewed the results of seven separate trials on screening and produced the following conclusion:-

Screening for breast cancer with mammography

The review includes seven trials involving a total of half a million women. The review found that mammography screening for breast cancer likely reduces breast cancer mortality, but the magnitude of the effect is uncertain and screening will also result in some women getting a cancer diagnosis even though their cancer would not have led to death or sickness. Currently, it is not possible to tell which women these are, and they are therefore likely to have breasts and lumps removed and to receive radiotherapy unnecessarily. ............ Screening also leads to overdiagnosis and over treatment.............. This means that for every 2000 women invited for screening throughout 10 years, one will have her life prolonged. In addition, 10 healthy women, who would not have been diagnosed if there had not been screening, will be diagnosed as breast cancer patients and will be treated unnecessarily. It is thus not clear whether screening does more good than harm.

TO BE SCREENED OR NOT?

Attending for screening is a very important decision for every woman who reaches the age of 50 (at present, there is no scientific evidence to support the benefits of screening women under this age). It should not be taken lightly and many factors will influence a woman’s decision to attend for screening e.g. a family history of breast cancer; a neighbour or friend whose cancer was picked up at screening; an unfounded but nevertheless very real anxiety of breast cancer which could be alleviated by an “all clear” screen.

In Scotland, it is a woman’s right to be screened for breast cancer and SBCC will continue to support this right. But with this ‘right’ comes choice – informed choice. When you are called for screening, take responsibility for your own health and make an “informed choice”.