In the herein investigated cohort, we have previously found high B cell density to be an independent favorable prognostic factor.10 Previous studies have demonstrated that B cells are required for optimal cell-mediated anti-tumor immunity,16 and in ovarian cancer, CD20+ B cells have been suggested to support CD8+ T cells in tumor immune response.17 Collectively, the findings from the present study suggest that pre-diagnostic obesity promotes CRC with a more favorable tumor immune microenvironment, defined by high infiltration of CD8+ T cells and CD20+ B cells. Here, CD8A is linked to ovarian cancer.