• JAMA Viewpoints on mammography guidelines:

    The first is “Breast Cancer Screening: Conflicting Guidelines and Medicolegal Risk“. I expected it to spend most of its time warning docs that if they followed guidelines they’d expose themselves to risk. But I was pleasantly surprised to find it quite balanced:

    It may be tempting to reason that more frequent mammography and CBE reduces the risk of being sued by decreasing the likelihood of missing an early diagnosis of breast cancer. However, clinicians must weigh this possible medicolegal benefit against 3 countervailing considerations. First, mammography can involve physical and emotional harm to patients, especially due to false-positive results. Second, at a population level, the gain in detection comes at a significant price. Performing CBE costs less, but may lead to additional follow-up imaging costs and undue worry for patients, and it detects relatively few cases of cancer that would be missed with regular mammography. Third, recent evidence suggests that despite its effectiveness in detecting early-stage breast cancer, screening mammography may have only small effects on breast cancer mortality.

    The USPSTF’s recommendation was based on the finding that biennial mammography “produced 70% to 99% of the benefit of annual screening, with a significant reduction in the number of mammograms required and therefore a decreased risk for harms.” One interpretation of the USPSTF’s recommendation is that at both the patient level and the societal level, the marginal benefit from additional screening is outweighed by the harm. But a plaintiff’s attorney might still argue that the USPSTF is conceding that biannual screening is less effective than annual screening in detecting cancer. While physicians may be justified in ordering mammograms less frequently, they may be concerned about how well the attorney’s argument might play before a jury. What should physicians do in situations like this?

    Worth a read.

    The second is “Sorting Through the Arguments on Breast Screening“. Again, go read the whole thing. The last paragraph really caught my eye:

    It is a worthy aim to have guidelines by which to assess the merits, or otherwise, of screening. The UK panel’s procedure did not differ greatly from these—with the single exception of feeling unable to gauge numerically the strength of the evidence. Reactions to the panel’s report suggest that those who had hitherto been confused by the divergence of views found the report helpful—as close as could be to a dispassionate view of the evidence by an independent panel. It is doubtful, however, that the independent panel changed the minds of the principal proscreening and antiscreening groups in the debate over screening. Positions are too entrenched. But the evidence on breast screening is more extensive than in many other areas relevant to population health. If this is not enough for an independent group, coming fresh to the debate, to reach a reasonable judgment, then evidence-based policy is a good deal more difficult than many would believe.

    Those last few sentences are sobering.


    • 1) Mammograms can be obtained at a relatively inexpensive price and in some areas for free at special times. Thus the financial burden of a mammogram is not that great for the vast majority of people. Self pay for this relatively inexpensive procedure would eliminate a lot of this debate. Patients would likely skip the marginal exam and perhaps a lot of the costs created by the mammogram. There would be no legal issue because it would be the patient’s decision and not the doctor’s.

      2) Policy makers should pay special attention to the last quoted sentence: “then evidence-based policy is a good deal more difficult than many would believe.” IMO that is true.

    • The second article is by Michael Marmot, one of the most famous UK epidemiologists, particularly for his work on social status and health. I’ve been to some of his talks.I’ll read his views on the screening debate with great interest.