Axillary staging prior to neoadjuvant chemotherapy for breast cancer: predictors of recurrence.

Abstract

The value of axillary staging prior to delivery of neoadjuvant chemotherapy (NEO) for breast cancer is controversial. Our goal was to analyze the prognostic and therapeutic impact of axillary staging on recurrence. The study cohort included 161 patients undergoing comprehensive evaluation by a multidisciplinary approach during the period 1996-2006. Clinicopathologic features were assessed before and after delivery of NEO. Patients with node-positive disease before NEO underwent a post-NEO axillary lymph node dissection at time of definitive breast surgery. At presentation, median age was 49 years; mean tumor size was 45 mm. The axilla was negative in 45 (28.6%) patients. Of the 114 pre-NEO node-positive patients, 65 (57%) were staged histologically. At completion of NEO, partial or complete clinical response was observed in 90.6%; complete pathologic response occurred in 23.6%. Mean residual tumor size was 10.5 mm. Of the 112 initially node-positive patients, 36 (31.6%) had no residual axillary disease post NEO. At median follow-up of 38.1 months, 21.7% patients relapsed. The pre-NEO nodal status was the strongest predictor of treatment failure. A significant risk of distant relapse was based on nodal response to NEO: 8.1% in node-negative patients, 13.9% in the downstaged group, and 22.1% in the persistently positive group (P = 0.047). Delivery of nodal irradiation decreased local recurrence in the downstaged group (12.5% versus 3.7%, P = NS). Our experience suggests that comprehensive axillary staging with ultrasound and fine-needle aspiration (FNA) and sentinel lymph node biopsy prior to NEO is both prognostically and therapeutically important in predicting those patients at higher risk of recurrence.