Clinicopathological and Endoscopic Features of Raspberry-Shaped Gastric Cancer in Helicobacter pylori-Uninfected Patients.

Background: Gastric adenocarcinoma of foveolar type (GA-FV) is a raspberry-shaped gastric cancer (RSGC) and garners much attention as H. pylori (Hp)-uninfected gastric cancer. However, the classification and clinicopathological and endoscopic features of RSGCs in Hp-uninfected patients are poorly defined. We designed a new histopathological classification of RSGC and compared them via endoscopic and clinicopathological characteristics.

Summary: From 996 patients with early gastric cancers resected by endoscopy in our hospital, we studied 24 RSGC lesions from 21 (2.4%) Hp-uninfected patients. RSGCs were classified into 3 histological types as follows: GA-FV (n = 19), gastric adenocarcinoma of fundic gland type (GA-FG, n = 2), and gastric adenocarcinoma of fundic gland mucosa type (GA-FGM, n = 3). Most of the lesions were found at the greater curvature of the upper or middle third of the stomach. GA-FV lesions were homogeneously reddish and frequently accompanied with a whitish area around the tumor and an irregular microvascular (MV) pattern; these features were confirmed histopathologically by the presence of homogeneous neoplastic foveolar epithelium with foveolar hyperplasia around the tumors. GA-FG lesions might be heterogeneously reddish with a submucosal tumor shape and regular MV pattern; these were confirmed by the presence of covered or mixed nonneoplastic epithelium on deeper regions of tumors. GA-FGM lesions might be homogeneously reddish and occasionally had a submucosal tumor shape and irregular MV pattern; these were confirmed by the presence of homogeneous neoplastic foveolar epithelium on deeper regions of the tumors. Key Messages: RSGCs in Hp-uninfected patients are classified into 3 histopathological types. For accurate diagnosis of RSGCs, it may be necessary to fully understand endoscopic features of these lesions based on these histological characteristics and to take a precise biopsy.