Surgeon-related variability in the outcome of cancer surgery.

Statistical and clinical differences between reports of surgical therapy are usually ascribed to differences in the named method of treatment. However, it is becoming increasingly clear that surgeons vary in the ability to produce a given result; this phenomenon is sometimes referred to as "surgeon-related variability." Thus surgical treatment should be seen as the resultant vector of the named procedure plus the effect of such surgeon-related variability. These propositions have significance for the conduct of prospective randomized controlled trials which set out to test the efficacy of alternative surgical treatments. These issues are of particular importance in the cancer field because therapy is becoming more commonly multiphasic and includes both medical and surgical treatments.