Comparison of Clinicopathologic Parameters and Survivals Between Epstein-Barr Virus-positive and Her2-positive Gastric Cancers.

Gastric carcinomas are highly mortal neoplasms for which new therapeutic options are being searched. The molecular subtyping of gastric adenocarcinomas was proposed recently, and the relationship between etiopathogenetic types is still under investigation. Here we compared histopathologic, prognostic, and survival differences between Epstein-Barr virus (EBV)-positive and Her2-positive gastric adenocarcinomas. In a retrospective design, we searched the EBV status with Epstein Barr Virus encoded small RNA (EBER) in situ hybridization, and the Her2 status both by immunohistochemistry and by chromogenic in situ hybridization of 106 gastrectomized gastric carcinomas. Histologic and clinical prognostic parameters and survival information were determined, and retrieved from archival tissues and clinical notes. The Her2 positivity rate was 12.3% and the EBV positivity rate was 7.6%. Among EBER-positive cases, Her2 positivity was not detected. Her2 positivity was detected more in intestinal differentiated tumors, whereas EBER positivity was detected in undifferentiated tumors (P=0.003). There was no correlation of Her2 or EBER positivity with the tumor stage. Median survivals of EBER-positive, Her2-positive, and both negative cases were 11.5, 18, and 20.5 months, respectively. The tumor stage and distant metastasis were found to be significant for survival in the multivariate analysis. In our 106 gastrectomized gastric carcinoma cases, EBV-positive and Her2-positive groups were found to be unrelated as proposed in the upcoming classification of gastric carcinomas.