Immunohistochemical features and staging of early gastric cancer

INTRODUCTION: The aim of this study was to analyze the particularities of early gastric cancer (EGC) and their importance for staging, prognosis, and therapy. MATERIAL AND METHODS: A total of 338 GCs diagnosed and surgically removed in three medical institutes from Eastern Europe were retrospectively examined, and the EGCs were further examined. Besides the demographic factors and tumor characteristics, immunostains were performed with E-cadherin, HER-2, p53, Ki67, MLH-1, MSH-2, COX-2, VEGF-A, CD31, and CD105. RESULTS: From the 338 GCs, 29 were EGCs, the average being similar in Poland and Hungary (12.37% and 13.33% respectively) but lower in Romania (5.61%). The rate of lymph node metastases was 20.69% (n = 6). Two of the cases presented liver metastases, both of them having a multifocal aspect. In 1 of these cases, limited to the mucosa, intramural carcinomatosis of the lymph vessels was seen in submucosa, muscularis propria, and subserosa. COX-2 positivity was observed in 14 (48.72%) cases. COX-2 was directly correlated with microvessel density determined with CD31 (p < 0.001) and CD105 (p = 0.03). Same correlation with CD31 and CD105 was seen for HER-2 (p = 0.03 and p = 0.0007). The only negative independent prognostic factors for overall survival were tumor localization at the proximal stomach and male gender, regardless of age. CONCLUSIONS: In EGCs, intramural carcinomatosis of the lymph vessels and multifocality should be separately described in every surgical pathology report, as indicators of aggressiveness. Microsatellite status, E-cadherin, HER-2, p53, and Ki67 do not have prognostic value in EGC, but the highly angiogenic pattern is a possible therapeutic target.