Patient reported outcomes following breast conserving surgery are improved by minimizing re-excisions and excessive breast tissue removal.

Background: Patient reported outcomes (PRO's) are a valuable tool in obtaining the patients' perspective on the effectiveness of breast conservation surgery. Investigation has primarily been focused on patient and disease related factors impacting PRO's, with a limited focus on surgically modifiable factors. We investigate the impact that the volume of breast tissue removed, and performance of re-excisions have on PRO's.

Methods: Retrospective evaluation of the BREAST-Q (breast conservation module) in patients undergoing breast conserving surgery over a 3 year period. Multivariate analysis of patient, disease, and treatment related factors impacting PRO's.

Results: 163 patients completed the BREAST-Q. The median satisfaction with breast score was 67 (IQR, 48-88). Increasing volume of resected breast tissue was negatively associated with appearance of the breast (-0.05/cm (CI; -0.08 to -0.01)), as was the performance of re-excisions (-6.59 (CI; -14.73 - 0)). Physical well-being of chest was negatively associated with the volume of breast tissue removed (-0.05/cm3 (CI; -0.08 - 0)), but not re-excisions. Psychosocial well-being was negatively affected by the volume of tissue removed ((-0.04/cm(CI; -0.07 - 0)), and re-excisions (-2.88 (CI; -10.96 - 0)). Patient body mass index, disease stage, receipt of Tamoxifen, as well as axillary lymph node dissection also impacted BREAST-Q domain scores.

Conclusion: The removal of larger volumes of breast tissue and performance of re-excisions negatively impact patient quality of life and breast satisfaction following breast conserving surgery. Optimal patient reported outcomes are associated with accurate tumour removal, which minimizes re-excisions and the removal of normal breast tissue.