Neoadjuvant Chemotherapy in Invasive Lobular Carcinoma May Not Improve Rates of Breast Conservation

Abstract

Patients with invasive lobular carcinoma (ILC) experience a lower pathological complete response rate to neoadjuvant chemotherapy than patients with invasive ductal carcinoma. This study was intended to evaluate the impact of neoadjuvant chemotherapy in ILC on breast-conserving surgery (BCS) rates. Two-hundred eighty-four consecutive patients with pure ILC treated between May 1998 and September 2006 were reviewed. Surgical procedures and long-term outcomes were compared between patients receiving neoadjuvant chemotherapy and those receiving surgery first. Neoadjuvant chemotherapy was administered to 84 patients; 200 patients underwent surgery first. The mean tumor size in the neoadjuvant group (4.9 cm) was significantly larger than in patients who underwent surgery first (2.5 cm, p < 0.0001). In the neoadjuvant group, clinical complete response was seen in 10% and partial response in 59%. Overall BCS rates were 17% in the neoadjuvant group compared with 43% in the surgery-first group (p < 0.0001). When controlled for initial tumor size, there was no difference (all p > 0.05) between the groups in terms of (1) the proportion of patients who underwent an initial attempt at BCS, (2) rate of failure of BCS or (3) the proportion of patients undergoing BCS as their final procedure. With a mean follow-up of 47 months, local recurrence (LR) rates were similar between the two groups (1.2% versus 0.5%, p = 0.5). The use of neoadjuvant chemotherapy does not increase the rates of breast conservation in patients with pure ILC.