Professor who set up the first breast screening centre in the UK says that the introduction of screening increases the incidence of breast cancer by 50 per cent
Women who are invited to get screened for breast cancer are unaware that the harms of breast screening are greater than the benefits. This is the assumption made by Professor Michael Baum from the School of Life and Medical Sciences, University College London, at a lecture that marked Breast Cancer Awareness Month (October).
The NHS Cancer Screening Programme distributes leaflets to women aged over 50 in order to persuade them to schedule a screening. However, an article released by the British Medical Journal (BMJ) in early 2009 reported “what the leaflets don’t tell patients”. Prof Baum calls for attention from the Department of Health. “It is shameful and disgusting that women are denied the opportunity to learn the truth about screening”.
The New England Journal of Medicine has reported that one breast cancer death is avoided for every 2,500 women older than 50 screened for 10 years. Also a report from the the Cochrance Centre – a centre that focuses on medical evidence for treatments – estimates that for every breast cancer death avoided, 10 women are over-diagnosed. The UCL Professor reacts: “Against that, one thousand women will have at least one false alarm and five to 15 women will be treated unnecessarily for a disease that would never threat their lives.”
According to Professor of Medicine H. Gilbert Welch, over-diagnosis of cancer “occurs when the cancer regresses or when the cancer grows so slowly that the patient dies of other causes before it produces symptoms”. Because doctors don’t know which patients are over-diagnosed, unnecessary treatment and mastectomies often happen.
Screening theory says that catching an early, small tumours leads to a fall in the incidence of late cancer. Yet Prof Baum considers that early cancers do you mean tumours? are often inoffensive. “The really nasty fish, the sharks that will kill you slip through the net – and those are called cancers.”
The expert, whose mother died from breast cancer and whose sister also developed the disease, does not suggest that “we shut down screening”; instead, he recommends that there should be a “risk management campaign” making women aware that they are at a much higher risk of having cardiovascular disease than breast cancer.
When the NHS screening programme was established in 1998, it followed a report of 1987 that stated breast cancer mortality had been reduced by 25 per cent in the 1970s, when the trials were made. In the meantime, treatment has improved and the survival percentage rose to up to 85 per cent. Therefore, Prof Baum believes that improvements due to screening are becoming “narrower and narrower”.