Tumor-infiltrating lymphocytes in breast cancer: A new predictor for responses to therapy.

We have prospectively validated in an independent clinical cohort the finding that elevated amounts of tumor-infiltrating lymphocytes in breast carcinoma tissues predict the response of patients to neoadjuvant chemotherapy. These results suggest that a robust tumor infiltration by T and B cells is a promising biomarker to define patients who might benefit from neoadjuvant chemotherapy.