LAUSR

Objective: The objective of this study was to document changes in physician practice structure among surgeons who treat women with breast cancer. Design: We merged cancer registry records from 5 large states with Medicare Part B claims to identify each surgeon who treated women with breast cancer. We added information from SK&A surveys and extensive internet searches. We analyzed changes in breast surgeons’ practice structure over time. Measures: We assigned each surgeon-year a practice structure type: (1) small single-specialty practice; (2) single-specialty surgery or multispecialty practice with ownership in an ambulatory surgery center (ASC); (3) physician-owned hospital; (4) multispecialty; (5) employed. Results: In 2003, nearly 74% of breast cancer surgeons belonged to small single-specialty practices. By 2014, this percentage fell to 51%. A shift to being employed (vertical integration) accounted for only a portion of this decline; between 2003 and 2014, the percentage of surgeons who were employed increased from 10% to 20%. The remainder of this decline is due to surgeons opting to acquire ownership in an ASC or a specialty hospital. Between 2003 and 2014, the percentage of surgeons with ownership in an ASC or specialty hospital increased from 4% to 17%. Conclusions: Dramatic changes in surgeon practice structure occurred between 2003 and 2014 across the 5 states we examined. The most notable was the sharp decline in the prevalence of the small single-specialty practice and large increases in the proportion of surgeons either employed or with ownership in ACSs or hospitals.