Effect of Neoadjuvant Chemotherapy on the Surgical Treatment of Patients With Locally Advanced Breast Cancer Requiring Initial Mastectomy.

BACKGROUND: The aim of this study was to assess the rate of breast-conserving surgery (BCS) after neoadjuvant chemotherapy (nCT) in patients for whom mastectomy (MT) was, initially, the only conceivable surgical option.

PATIENTS AND METHODS: Between 2007 and 2012, 168 patients from a single center received nCT. Among these patients, we focused on the ones who received nCT (n = 119, [70.8%]) to decrease tumor size and thus to potentially allow a conservative surgical treatment. For these patients, MT was initially the only possible surgical treatment.

RESULTS: Among the 119 patients included, 118 presented with an invasive ductal carcinoma. The mean tumor size before nCT, measured using magnetic resonance imaging, was 41.6 mm (range, 15-110 mm) and 25.3 mm (range, 0-90 mm) after nCT. Eighty-six patients (72.3%) underwent BCS, and oncoplastic techniques were used in 29 patients (33.6%). Only 4.3% (5 patients) of patients who were treated with BCS needed additional surgery because of positive surgical margins. The median follow-up was 41.1 months (95% confidence interval [CI], 35.2-48.3). Five-year overall survival after BCS and MT were 77% (95% CI, 63-92) and 77% (95% CI, 63-95) respectively. Five-year disease-free survival after BCS and MT were 74% (95% CI, 64-86) and 59% (95% CI, 40-89) (not significant), respectively.

CONCLUSION: nCT for selective patients with "chemosensitive" breast tumor leads to a significant "MT to BCS" conversion rate. The type of surgery does not seem to affect the patient's overall and disease-free survival rates. Oncoplastic procedures can help to extend BCS after nCT.