Characteristics of non-neoplastic epithelium that appears within gastric cancer with and without Helicobacter pylori eradication

A non-neoplastic epithelium (NE) often appears in gastric cancer (GC). We explored the histological features of NE in comparison between HP-eradicated and HP-infected GCs. We enrolled 40 HP-eradicated and 40 HP-infected GCs matched by size, macroscopic and histological type. NE was classified into full gland type and surface type; the former was a non-neoplastic gland isolated within cancer, and the latter was NE on the surface of the cancer. Surface type was additionally divided into NE at the cancer margin (marginal surface type) and NE inside cancer (internal surface type). The primary endpoints were the frequency and the length ratio (the ratio to cancer length) of NE in each GC. The secondary endpoints were the relationships between NE and clinicopathological factors, including endoscopic findings of a gastritis-like appearance (GLA), multiple white elevated lesions (MWELs), reddish depressed lesion (RDL), and white nodular mucosa (WNM). The frequency and length ratio of the intern...