CD4 and neoplasm: T cells represent the 34.8% of the tumor infiltrating cells (range 19.7-51.3%; n=8 PDAC), with CD8+ and CD4+ T cells counting for the 19.6% (range 8.4-32.2%; n=8) and 15.19% (range 5.1-26.2%; n=8) of T lymphocytes, respectively (Figures 3B, C: CD3+, CD8-, white arrowheads, CD3+, CD8+, white arrows).