New prognostic factors in gastric cancer: the role of lympho-plasmacytic infiltrate.

BACKGROUND:Gastric cancer triggers an immune response, manifested by immunocompetent cells infiltrating the tumor, such as macrophages, NK cells, neutrophils, T and B-lymphocytes, and plasma cells. METHODS:Were viewed 300 patients who received surgery for gastric cancer, with removal of at least 15 regional lymph nodes, from January 1998 through December 2008, at the Policlinico "Umberto I", Department of Surgery "Pietro Valdoni", "Sapienza" University of Rome, and at "Santa Maria Goretti" Hospital of Latina, Italy. We selected a subset of 46 patients identified according to the following selection criteria: presence of gastric cancer (both intestinal-type and diffuse-type), early-stage (T1 and T2), absence of nodal metastases (N0), or involvement of less than 8 lymph nodes (N1), absence of distant metastases (M0), stage I and II. The sample included 28 males and 18 females. RESULTS AND CONCLUSIONS:Our results suggest that a high number of tumour-associated macrophages (TAM) along the margins of the tumour is related to a worse outcome, and an increased secretion of immunosuppressive cytokines by TAM may also indirectly affect the action of cytotoxic T cells. Our study also shows a statistically non significant trend of tumour-associated macrophages in promoting the expression of β-catenin, which is a subunit of the cadherin protein complex. KEY WORDS:Gastric cancer, Infiltrate, Lymphoplasmacellular, Prognostic factors, TNM.