Breast cancer screening review

Yesterday, the media reported that following an open letter by Susan Bewley, professor of complex obstetrics at King's College London, to the government's cancer chief, an independent investigation into breast cancer screening has been set up to try to settle the growing controversy around its benefits and potential harms.

The NHS Breast Cancer Screening Programme began in 1988 and claimed that the scientific evidence demonstrates clearly that regular mammographic screening between the ages of 50 and 70 reduces mortality from the malignancy.

The 1st systematic review of breast cancer screening came from the Nordic Cochrane Centre, part of the Cochrane Collaboration, published in The Lancet in 2000. The review was based of 8 large RCTs with more than 182,000 women in the Nordic countries. The authors found that the quality of the trials were low and the data showed that for every 1000 women screened biennially throughout 12 years, only 1 breast-cancer death was avoided whereas the total number of deaths was increased by 6. The authors concluded that "Screening for breast cancer with mammography is unjustified".

The most recent update of this review was published on 19 January 2011. The authors said that it is not clear whether screening does more good than harm and women invited to screening should be fully informed of both the benefits and harms.

Source: Gøtzsche PC, Nielsen M. Screening for breast cancer with mammography. Cochrane Database of Systematic Reviews 2011, Issue 1

Breast cancer screening controversy

The US Preventive Services Task Force (USPSTF) has issued new guidelines calling for women to change from annual screening at age 40 to biennial mammograms at 50.

The new guidelines aimed at reducing unnecessary treatment but have caused public uproar and confusion. Radiologists say the USPSTF recommendations were "unfounded" and put forward their own guidelines in the January issue of the Journal of the American College of Radiology.

However, the USPSTF continues to recommend biennial mammograms and says that individuals should take into account one's values regarding specific benefits and harms when deciding when to start the screening.

Source: "Screening for breast cancer: U. S. Preventive Services Task Force recommendation statement" Ann Intern Med 2009; 151: 716-26.