Characterizing TIL composition allows monitoring of immunotherapies and can be a prognostic factor for clinical outcome. Here we analyze the phenotype and function of lymphocytes collected from peripheral blood and tumor infiltrating lymphocytes, immediately following resection, from 15 patients with colorectal cancer liver metastases (CRLM) and 21 ovarian cancer primary tumors (OVC). Samples were analyzed using a multi-color flow panel and by qPCR for cytokine production. The percentage of different lymphocyte subpopulations was similar in both patients. Highly suppressive Tregs expressing HLA-DR were significantly increased in TIL compared to PBL in CRLM: 69.4% vs 31.7% (p=0.0002) and in OVC: 74.8% versus 38.6% (p