Call for review of breast screening

Growing doubts over the value of breast screening are now causing so much dissension within the medical community that an international study is needed to resolve the issue, a leading medical journal says today.

Billions of pounds are being spent worldwide on screening programmes to cut deaths from breast cancer, and millions of women are subjected to the discomfort and anxiety of waiting for their results and being recalled for follow-up tests. Yet doctors still disagree on the benefits.

The dispute over screening broke out last October when The Lancet published an article by two Danish scientists who had earlier caused an outcry by suggesting breast screening did not save lives. Peter Gotzsche and Ole Olsen repeated their analysis and said they were now even more sure their earlier claims were correct. They reviewed seven trials involving 450,000 women and concluded the small difference in deaths was caused by the way the trials were designed, not by screening.

The findings were rejected in Britain by the NHS national screening programme, which claimed breast screening had saved thousands of lives, but they caused a furore in America. The issue dominated the American front pages in December, prompting cancer organisations to take out a full-page advertisement in The New York Times reassuring women of the importance of mammography.

The Physicians Data Query board, which advises the US National Cancer Institute (NCI), reported in January that all seven major mammography studies were seriously flawed and that "mammograms may not be beneficial". However, the NCI later announced it had rejected the PDQ board's advice. Last week, the US Health Secretary, Tommy Thompson, reiterated the message. "If you are 40 or older, get screened for breast cancer every one to two years," he said.

On January 27, The New York Times ran an editorial highlighting the financial incentives at work. It called for a review of the evidence but the NCI and the American Cancer Society insisted breast screening must continue. However, the American Society of Clinical Oncology announced it would convene a panel of experts to review the data.

In an editorial published today, The Lancet Oncology, a specialist cancer journal published by The Lancet, says: "What has emerged from the opposing views is the need for a thorough reappraisal of breast cancer screening."