Surgeon Variability and Factors Predicting for Reoperation Following Breast-Conserving Surgery.

Background: Reoperation after breast-conserving surgery (BCS) is common and has been partially associated with the lack of consensus on margin definition. We sought to investigate factors associated with reoperations and variation in reoperation rates across breast surgeons at our cancer center.

Methods: Retrospective analyses of patients with clinical stage I-II breast cancer who underwent BCS between January and December 2014 were conducted prior to the recommendation of 'no ink on tumor' margin. Patient demographics and tumor and surgical data were extracted from medical records. A multivariate regression model was used to identify factors associated with reoperation.

Results: Overall, 490 patients with stage I (n  = 408) and stage II (n  = 89) breast cancer underwent BCS; seven patients had bilateral breast cancer and underwent bilateral BCS procedures. Median invasive tumor size was 1.1 cm, reoperation rate was 22.9% (n  = 114) and varied among surgeons (range 15-40%), and, in 100 (88%) patients, the second procedure was re-excision, followed by unilateral mastectomy (n  = 7, 6%) and bilateral mastectomy (n  = 7, 6%). Intraoperative margin techniques (global cavity or targeted shaves) were utilized in 50.1% of cases, while no specific margin technique was utilized in 49.9% of cases. Median total specimen size was 65.8 cm (range 24.5-156.0). In the adjusted model, patients with multifocal disease were more likely to undergo reoperation [odds ratio (OR) 5.78, 95% confidence interval (CI) 2.17-15.42]. In addition, two surgeons were found to have significantly higher reoperation rates (OR 6.41, 95% CI 1.94-21.22; OR 3.41, 95% CI 1.07-10.85).

Conclusions: Examination of BCS demonstrated variability in reoperation rates and margin practices among our breast surgeons. Future trials should look at surgeon-specific factors that may predict for reoperations.