Contrary To Conventional Wisdom, Physicians Abandoned A Breast Cancer Treatment After A Trial Concluded It Was Ineffective

Conventional wisdom holds that physicians are slow to abandon ineffective medical practices. We evaluated this theory in the case of axillary lymph node dissection, a procedure to remove the lymph nodes near the breast to prevent the spread of breast cancer following breast-conserving surgery. A major trial conducted from 1999 to 2004, with results presented in 2010 and published in 2011, found that patients who met certain criteria could forgo axillary lymph node dissection. Using cancer registry data, we estimated that the proportion of patients undergoing axillary dissection declined by 32.6 percentage points after the trial was published. The decline began immediately after the trial was presented at a medical conference. The rapid decline in the use of axillary dissection belies the common belief that practice patterns are slow to change in response to new evidence, and it highlights the value of trials of established medical practices to patients and the health system.