Feasibility of breast conservation surgery in locally advanced breast cancer downstaged by neoadjuvant chemotherapy: A study in mastectomy specimens using simulation lumpectomy

Abstract

BACKGROUND: The response of locally advanced breast cancer (LABC) to neoadjuvant chemotherapy (NACT) offers these patients previously treated by mastectomy, the chance for breast conservation. AIM: This study aims to assess the feasibility of lumpectomy in patients with LABC treated by NACT, with residual tumor 64 5 cm. SETTINGS, DESIGN: Single group prospective study from August 2001 to June 2003 in a teaching hospital. MATERIALS AND METHODS: Thirty patients with LABC whose tumors reduced with NACT to 64 5 cm were included. Simulation lumpectomy was performed on the mastectomy specimens to achieve 1 to 2 cm clearance from tumor and hence margin negativity. Multiple sections of the inked margin were studied. STATISTICAL ANALYSIS: Margin positivity was correlated with patient factors. Chi square test and Fisher\u2032s exact test used as appropriate. P value 64 0.05 was considered significant. RESULTS AND CONCLUSIONS: After three cycles of NACT, 4 patients (13%) had complete clinical response including 2 with complete pathological response. Twenty-two (73%) showed partial response and 4, no response. Fourteen out of thirty (47%) had tumor involvement of margins. Tumors with post-chemotherapy size >4 cm were margin positive in 10/13 (77%). Tumors with post-chemotherapy size >3 cm were margin positive in 13/24 (54%). Tumors with post-chemotherapy size 64 3 cm were margin negative in 5/6 (83%). Pre-chemotherapy tumor size and post-chemotherapy tumor size were significantly associated with margin positivity (P=0.003). Tumors in the subareolar location had significantly higher incidence of residual tumor in the nipple areola complex. (P=0.04). Margin positivity of lumpectomy on downstaged tumors can be reduced by removing the nipple areola complex in subareolar tumors and by limiting breast conservation to tumors with post-chemotherapy size 64 3 cm