Intratumoral CD68-, CD117-, CD56-, and CD1a-positive immune cells and the survival of Iranian patients with non-metastatic intestinal-type gastric carcinoma.

The purpose of this study was to investigate the prognostic significance of intratumoral immune cell counts in Iranian gastric cancer patients. A historical cohort study was conducted on fifty patients with non-metastatic intestinal-type gastric adenocarcinoma who underwent curative gastrectomy during 2004-2008 in Imam-Reza Hospital, Mashhad University of Medical Sciences. Immunohistochemistry (IHC) staining for CD56, CD68, CD117 and CD1a was performed to detect natural killer cells, macrophages, mast cells and Langerhans cells, respectively. The immune cells were counted, and the patients were then stratified into low or high immune cell counts. The prognostic significance of this grouping was analyzed using the Kaplan Meier method and Cox proportional hazards regression modeling. Thirty eight (76%) male and twelve (24%) female patients were enrolled in the study with a mean (±SD) age of 66.0 (±9.2) years. The median survival time was 15.0 (95%CI: 5.5-24.5) months. Natural killer cells, mast cells and Langerhans cells showed a positive effect on survival, whereas the reverse was true for macrophages. Multivariate analysis showed that the independent prognostic factors were location of the tumor (cardia/non-cardia), stage, the presence of extra-cytoplasmic mucin, tumor associated macrophage status (low/high), and tumor associated Langerhans cell status (low/high). In the studied population, gastric carcinoma proved to have a very poor prognosis. Multivariate analysis showed that the prognostic effect of natural killer and mast cells in tumoral tissue were dependent on the Langerhans cell count, defending the theory that dendritic cells mediate other immunocytes activities.