Immune-cell infiltration in high-grade soft tissue sarcomas; prognostic implications of tumor-associated macrophages and B-cells.

We confirm that tumor-infiltrating macrophages outnumber tumor-infiltrating lymphocytes in soft tissue sarcoma and signify an increased risk of metastasis. CD20 B-cells are scarce in STS and correlate to improved survival. To date, immunotherapeutic strategies directed against T-cells have shown limited effect in soft tissue sarcoma. Our observations suggest that immunomodulatory agents focusing on macrophages may be worthwhile for further investigations in this tumor type. Further studies exploring the prognostic and predictive significance of CD20 B cells are warranted.