Background: Many believe that breast cancer should be treated by specialists. We studied the effect of surgeon and hospital specialization on survival after breast cancer treatment in a large, well-defined patient population.
Methods: The Cancer Surveillance Program database for Los Angeles County was reviewed. Between 1990 and 1998, 43,411 cases of breast cancer were diagnosed, of which 29,666 had complete data on surgeon, hospital, and staging information. Patients were stratified on the basis of surgeon and hospital specialization, as well as by age, race, stage, surgical procedure, and surgeon and hospital case volume. An analysis of survival and its dependence on these factors was performed.
Results: Age, race, socioeconomic status, tumor size, nodal status, extent of disease, surgeon specialization, surgeon case volume, and hospital case volume were all associated with 5-year survival after diagnosis of breast cancer. Treatment at a specialty center did not affect survival. Multivariate analysis indicated that type of surgeon was an independent predictor of survival (relative risk,.77), as were both hospital and surgeon case volume.
Conclusions: Treatment by a surgical oncologist resulted in a 33% reduction in the risk of death at 5 years. The effect of surgical specialization cannot be entirely attributed to volume effects.