Decentralization of breast cancer surgery in the United States.

BACKGROUND

Physician volume of at least 15-30 annual breast cancer operations has been associated with higher 5-year survival rates. The authors sought to determine whether surgical volumes for breast cancer in the United States frequently reach this threshold.

METHODS

The authors conducted a retrospective cohort study of 987 surgeons who operated on 8105 Medicare patients with breast cancer during 1994-1995 in 6 areas in the Surveillance, Epidemiology and End Results tumor registry. The 2-year physician volume of breast cancer operations was estimated among Medicare patients (approximating the on-average annual volumes for patients of all ages) and its association was examined with physician characteristics and with 3 measures of surgical care.

RESULTS

The median 2-year Medicare volume for breast cancer surgeons was 6, and 79% of physicians performed < or = 12 operations. Approximately 50% of patients were cared for by physicians who performed < or = 12 operations over 2 years, and 10% of patients were cared for by physicians who performed > or = 30 operations. Surgeon characteristics of age, female gender, general surgery board certification, and academic affiliation were associated with modestly higher volumes of breast cancer surgery. Higher surgeon volumes were associated with higher patient receipt of breast-conserving surgery, testing for hormone receptors, and lymph node dissection during mastectomy.

CONCLUSIONS

Most physicians who perform breast cancer surgery perform few annual operations in Medicare patients, and lower volumes are associated with differences in surgical processes of care. Because patients in the Medicare age group comprise almost 50% of all incident breast cancer cases, surgical volumes for patients of all ages also are likely to be low. It is likely that only approximately 10% of patients in the United States are treated by surgeons who performing at least 30 annual operations.