Keshtgar and colleagues tell the story of a team of breast surgeons who started out doing a routine cosmetic operation; then, an unexpected discovery of cancer led to a succession of further operations, including loss of the patient’s breast.1 They have misgivings about whether this surgery was of benefit and the experience threw up questions for them about cancer screening, the nature of consent, and the ethical dilemmas surrounding it. For me the striking feature is that they lacked evidence. It may not be easy to obtain such evidence, but it is surely the lack of evidence that is the root cause …