Two important articles on cancer screening have been published this week, one in the British Medical Journal (BMJ) and another in the Annals of Internal Medicine. Vinay Prasad, an oncologist from Portland, Oregon, was principal author of a paper in the BMJ entitled “Why cancer screening has never been shown to ‘save lives’ – and what we can do about it.” He and his co-authors reviewed the literature and asserted the argument that screening “saves lives” rests on reductions in disease-specific mortality rather than overall mortality.
Prasad et al. considered the evidence for the public’s perception of the benefits of screening for breast, cervical and prostate cancer, and showed there was an inflated sense of the benefits and a corresponding discounted sense of the harms. They said that properly randomized clinical trials, where the number of participants was increased ten-fold, would be required to determine whether screening saved lives. The paper ended with a quotation by Otis Brawley, chief medical officer of the American Cancer Society: “We must be honest about what we know, what we don’t know, and what we simply believe.”
Writing in the Annals of Internal Medicine, Albert Siu, on behalf of the United States Preventive Services Task Force (USPSTF), published a recommendation statement on screening for breast cancer. The USPSTF reviewed the evidence for: the effectiveness of screening in reducing breast cancer-specific and all-cause mortality; harms of screening; digital breast tomosynthesis (DBT) as a primary screening strategy; and adjunctive screening using ultrasound or magnetic resonance imaging.
The USPSTF recommended biennial screening with mammography for women aged 50 to 74, but for women between 40 and 50 the Task Force said the decision should be an individual one. They further concluded there was, as yet, insufficient evidence: to recommend screening for women over 75; to assess the benefits of DBT; and to judge the benefits and harms of adjunctive imaging. Kirsten Bibbins-Domingo, vice-chair of the USPSTF, said the latest recommendations aimed to clarify their 2009 guidelines, which were “widely misinterpreted as a recommendation against screening for women in their 40s.”
What are the implications for women in the USA and their insurance coverage, and for companies that manufacture the equipment used in screening? It turns out that Congress has mandated a two-year moratorium on implementation of any USPSTF recommendations, thus assuring mandatory insurance coverage for millions of American women. Hologic, manufacturers of the market-leading DBT system, has drawn attention to the Consolidated Appropriations Act of 2016, concluding that this is good news for both women and mammography.