Breast cancer screening pros and cons

Does breast cancer screening improve my chances of survival? Are there any disadvantages to screening? What happens if an abnormality is detected? To make a conscious decision to screen (or not), a woman must be clearly and fully informed in advance about the pros and cons and consequences of (not) screening. KCE prepared a set of neutral messages for women with a normal risk of breast cancer. Special attention was paid to making the message as understandable as possible, for all women. The material is to be used by anyone active in the field, in patient contacts or to be included in written documentation.

Usually from the age of 40, there is a chance that a woman, although she has no symptoms or close relatives with breast cancer, will receive the offer to be tested for breast cancer or ask for it herself. The offer may come from the gynecologist or family doctor. For the age group between 50 and 69, women are systematically invited from the government for the free biennial breast cancer screening.

In order to make a conscious decision about whether to be screened or not, women must receive clear and complete information in advance, and there appeared to be a need for this. The KCE collected all relevant existing scientific information, based on international studies and Belgian data. The result is a set of comprehensible information diagrams in which figures are presented as schematically as possible, and in which no position is taken for or against screening. The text was tested for intelligibility by a sample of women of all levels of education, in order to make it accessible to the largest possible number of women.

Large majority of women not at increased risk

The information is intended for the vast majority of women (94%) who are not at increased risk for breast cancer. Women at increased risk (e.g., with breast cancer in the family) or with symptoms, such as a lump in the breast, should consult their doctor for more information.

Risk of developing breast cancer varies significantly by age

1 woman in 8 will ever develop breast cancer. This figure is common knowledge and often causes concern. Therefore, nuance is needed. The figure reflects the risk over a lifetime, but there is a significant difference in risk by age group. For example, only 1 woman in 50 in the 40-49 age category develops breast cancer. Until the 60-69 age group, the risk increases, only to decrease again thereafter.

Benefit: Reduced mortality from breast cancer

Contrary to popular belief, screening cannot reduce the risk of breast cancer. It can, however, reduce the number of deaths because sometimes a cancer is detected earlier and treatment works better as a result.

Disadvantage: overtreatment and radiation

Women appear to be less aware of the disadvantages of breast cancer screening, yet a prerequisite for making an informed decision. One disadvantage is that screening also finds and treats "dormant" breast cancers. These are cancers that do not develop and would never have been detected without screening. Doctors cannot predict whether dormant cancers will ever wake up, and therefore treat all detected tumors just to be sure. In pre-menopausal women, mammography X-rays can also cause breast cancer. It is one of the reasons why systematic screening of women between the ages of 40-49 is not recommended by the government.

Utility of mammography and ultrasound together is not proven

The proposed information material deals only with the screening campaigns organized by the government, which meet European quality standards. About the screening performed by individual physicians, often with an additional ultrasound in addition to the mammography, this information material makes no statements. It is not recommended because its usefulness has not been proven.

KCE recommends that all agencies and individuals who promote and/or perform breast cancer screening provide women with comprehensible, complete information. Only in this way can women themselves, in greater freedom, make an informed decision.

Source: press release KCE