Repeat Surgery After Breast Conservation for the Treatment of Stage 0 to II Breast Carcinoma: A Report From the National Cancer Data Base, 2004-2010

IMPORTANCE: Although complete excision of breast cancer is accepted as the best means to reduce local recurrence and thereby improve survival, there is currently no standard margin width for breast conservation surgery. As a result, significant variability exists in the number of additional operations or repeat surgeries patients undergo to establish tumor-negative margins. OBJECTIVE: To determine the patient, tumor, and facility factors that influence repeat surgery rates in US patients undergoing breast conservation surgery. DESIGN, SETTING, AND PATIENTS: Patients diagnosed as having breast cancer at a Commission on Cancer accredited center from January 1, 2004, through December 31, 2010, and identified via the National Cancer Data Base, a large observational database, were included in the analysis. A total of 316 114 patients with stage 0 to II breast cancer who underwent initial breast conservation surgery were studied. Patients who were neoadjuvantly treated or whose conditions were diagnosed by excisional biopsy were excluded. MAIN OUTCOMES AND MEASURES: Patient, tumor, and facility factors associated with repeat surgeries. RESULTS: A total of 241 597 patients (76.4%) underwent a single lumpectomy, whereas 74 517 (23.6%) underwent at least 1 additional operation, of whom 46 250 (62.1%) underwent a completion lumpectomy and 28 267 (37.9%) underwent a mastectomy. The proportion of patients undergoing repeat surgery decreased slightly during the study period from 25.4% to 22.7% (P