Epstein-Barr virus-associated gastric carcinoma in the remnant stomach: de novo and metachronous gastric remnant carcinoma

Background. The remnant stomach corresponds to the gastric cardia, but is exposed to a completely different environment. The present study was performed to investigate the role of Epstein-Barr virus (EBV) infection in patients with gastric remnant carcinoma (GRC). Methods. Clinicopathological features, gastritis, and infection by EBV were investigated in patients with two types of GRC: GRC occurring at an interval of 10 years or longer between operations (de novo GRC group) and GRC occurring within 10 years after the initial operation for gastric carcinoma (metachronous GRC group). Results. EBV involvement in the de novo GRC group (23%) was not significantly different from that in the cardia of non-remnant carcinomas (controls; 18%). EBV involvement showed greater correlations in male patients (18/63; 28%), and in those with gastritis cystica polyposa (GCP; 13/41; 31%), and those with an interval of 20 years or longer (15/50; 30%) than with the other parameters. Multivariate analysis showed a significant correlation between GCP and EBV infection. Histologically, hyperplasia or mild atrophy, and mild lymphocytic infiltration were observed in 56% and 67% of non-neoplastic mucosa of EBV-associated GRC, respectively. In the metachronous GRC group, EBV-encoded mRNA in situ hybridization (EBER-ISH) of 27 pairs of primary gastric carcinomas (GCs) and metachronous GRCs indicated that only six EBV (+) metachronous GRCs were derived from EBV (+) GC. Conclusions. Epstein-Barr virus infection, together with long-standing inflammation, which causes GCP, may facilitate the development of de novo GRC. Close follow-up of patients treated with distal gastrectomy for EBV-associated GC is necessary to detect metachronous GRC.