Objective decision making between conventional and oncoplastic breast-conserving surgery or mastectomy: An aesthetic and functional prospective cohort study.

BACKGROUND: Breast-conserving surgery (BCS) is considered the standard treatment for early-stage breast cancer. However, fair to poor cosmetic outcomes following conventional BCS have been observed in as many as one-third of cases. The aim of this study was to determine the critical tumor-to-breast volume ratio for each quadrant of the breast beyond which conventional BCS would no longer offer acceptable cosmetic and functional results or satisfactory quality of life for the patient.

METHODS: A prospective cohort study was performed between December 2011 and December 2013 involving 350 patients younger than 70 years with early-stage unifocal (T ≤ 30 mm) breast cancer who underwent wide excision and axillary sentinel lymph node biopsy followed by whole-breast irradiation. Using validated panels and software (the Breast Cancer Treatment Outcome Scale [BCTOS], EORTC Cancer Quality of Life Questionnaire number C30-BR23, and Breast Cancer Conservative Treatment - cosmetic results [BCCT.core] software), quality of life and aesthetic and functional parameters and their changes in correlation to the percentage of breast volume excised were statistically analyzed.

RESULTS: The maximum percentages of breast volume that were resectable by conventional BCS without resulting in unacceptable aesthetic and functional outcomes or decreased quality of life were 18-19% in the upper-outer quadrant (p < 0.0001), 14-15% in the lower-outer quadrant (p < 0.0001), 8-9% in the upper-inner quadrant (p < 0.0001), and 9-10% in the lower-inner quadrant (p < 0.0001).

CONCLUSION: Aided by the calculated cut-off values for each breast quadrant, breast surgeons might render more objective decisions regarding performing conventional BCS, using oncoplastic techniques or choosing mastectomy with immediate reconstruction.