Lowering Re-excision Rates After Breast-Conserving Surgery: Unraveling the Intersection Between Surgeon Case Volumes and Techniques.

Abstract

The re-excision rates after breast-conserving surgery (BCS) are significantly varied, with surgeon case volume as one influential factor. Surgeons with higher case volumes have been shown to have lower reoperation rates. This study attempted to determine whether this may be attributable to excessive breast tissue removal during initial BCS. A retrospective study analyzed referrals to the authors' cancer center during 3years. Patients undergoing initial BCS for ductal carcinoma in situ or T1-T3 breast cancers were included. Patient age, tumor factors, surgeon case volume, and the calculated resection ratio (CRR) were analyzed. The total resection volume was divided by the optimal resection volume to produce the CRR, which reflected the magnitude of excess tissue resected during initial BCS. Comparison of the mean CRR between surgeon case-volume categories was performed with a repeated measures analysis of variance. A multivariate regression model assessed the effects of the CRR and surgeon case volume on re-excision rates. Larger tumor size, lobular histology, and lower CRR were associated with increased re-excision rates. The CRR was similar for each surgeon case-volume group. Surgeon case volume was not independently associated with re-excision rates, but surgeons with very high case volumes had lower odds of re-excision than surgeons with intermediate case volumes (odds ratio 0.44; 95% confidence interval 0.21-0.91). When control was used for the CRR, apparent differences in re-excision rates between surgeon case-volume groups were observed, suggesting that surgeons with higher case volumes may be more accurate when performing BCS.