Lymphocyte infiltration into solid tumors has been recognized as a main determinator of positive prognosis. For the most part this is attributed to cytotoxic T cells capable of directly destroying malignant cells. However, when considering the complex composition of the human immune system, recent findings of Nielsen et al on a potentially central role of tumor-infiltrating B cells is not really surprising. In this commentary article, I want to highlight the enormous potential impact of this observation for basic and translational research, prognostic procedures and ultimately for the development of future therapeutic concepts.
Keywords: CD20+ tumor-infiltrating lymphocytes; Functional immunology; Immunotherapy; Prognosis; Tumor-infiltrating B cells.