Abstract 701: TUMOR lymphocyte infiltration, expression of CD4, CD8, FOXP3, CD34 molecules and their relationship with tumor evolution after primary treatment in breast cancer patients

Considering that, approximately, only half of breast cancer patients respond to present therapies, a better knowledge of breast cancer biology, one of the most common neoplasms in women, will enable to design better therapeutic approaches. It has been proposed that different tumor characteristics like inflammatory infiltrate intensity, number of T regulatory (Tregs) cells and density of tumor vasculature could be useful to anticipate the response to therapy. Our aim was: a) to analyze the lymphocytic infiltrate and the expression of CD4, CD8, CD34 (endothelial marker) and Foxp3 (Treg marker) in primary tumors of breast cancer patients, and b) to relate them with clinical evolution (disease free: DF or relapsed: R) after 5 years from the primary treatment (surgery). There were analyzed archive samples of ductal mammary tumors (n=27), mostly in stages I and II. The expression of CD4 and CD8 in intra- and peri-tumoral lymphocytes was determined by immunohistochemistry (IHC) and confirmed by confocal microcopy; also the expression of Foxp3 in lymphocytes and tumor cells and CD34 in endothelial cells was evaluated by IHC. The lymphocytic infiltrate was assessed in histological sections stained with hematoxylin-eosin. The quantification was done in 20 high magnification fields and a score ranging from 0 (null) to 6 (high) was utilized. In DF patients (n=22) the intratumoral lymphocytic infiltrate (median [range]: 3 [0-6]) was more intense than that of R patients (n=5), (2 [0-2]), (P=0.05). For CD4, CD8, CD34 and Foxp3 molecules no differences between groups of patients were observed, being their expression highly variable: the score for CD34 varied from 1 to 6 and for the other three molecules from 0 to 6, in either group. In conclusion, the presence of an intense intratumoral lymphocytic infiltrate could be a prognostic marker of good response to treatment, at least in the first 5 years after surgery. These results warrant the study of higher number of tumor samples, since its confirmation could give support for its use in the clinical setting. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 701. doi:1538-7445.AM2012-701