Lymphopenia as a predictive factor of responsiveness to preoperative treatment in patients with locally advanced breast cancer.

Abstract

e21096 Background: It has been suggested that lymphopenia is an important prognostic factor for survival in patients with advanced breast cancer. The aim of this study was to evaluate if lymphopenia could be a predictive factor of responsiveness to preoperative treatment in patients with locally advanced breast cancer. Methods: We retrospectively evaluated 163 consecutive locally advanced (T3-4, N0-3, M0) breast cancers patients who received preoperative treatment in our hospital from January 2003 to December 2005. We classified them according to the subtypes: Luminal A, Luminal B, HER2 and Triple Negative (TN). The absolute lymphocyte count (ALC) was recorded at the time of diagnosis and a cutoff value of 1500/mm3 was used to define lymphopenia. Kaplan Meier, log-rank and pairwise comparisons were used to compared overall survival (OS) and time to treatment failure (TTP) between subtypes and to look for predictive factors of progression during preoperative treatment. Results: Of the 163 patients, 101 (62%) were Luminal A, 35 (21%) were TN, 18 (11%) were Luminal B and 9 (6%) were HER-2. OS and TTP were significantly lower for TN and HER2 subtypes compared to Luminal A. Only 33 patients (20.2%) progressed during preoperative treatment. 34% of TN patients progressed during preoperative treatment; 28% of Luminal B; 15% of Luminal A; and 11% of HER2 patients. Based on lab data 28 (17.2%) patients had an ALC <1500/mm3. Of these, 43% progressed during preoperative treatment. On the other hand 16% of the patients with an ALC ≥1500/mm3 progressed (p=0.001). Other variables such as age, clinical T, clinical N, histological grade, HER-2 status, ER status and breast cancer subtypes did not predict failure to preoperative treatment significantly. Conclusions: Lymphopenia at the time of diagnosis could predict progression during preoperative treatment in patients with locally advanced breast cancer. These results suggest that the host immune response could play an important role in the response of chemotherapy. Studies with larger numbers of patients are needed to validate these results.