Optimal biopsy site for Helicobacter pylori detection during endoscopic mucosectomy in patients with extensive gastric atrophy.

Helicobacter pylori eradication is essential for metachronous gastric cancer prevention in patients undergoing endoscopic mucosectomy (EMR). This study was aimed to determine the optimal biopsy site for H. pylori detection in the atrophic remnant mucosa of EMR patients. Data were analyzed from 91 EMR patients. Three paired biopsies for histology were taken at antrum, corpus lesser (CLC), and greater curve (CGC). Additional specimens were obtained at antrum and CGC for rapid urease test (RUT). H. pylori infection was defined as at least two positive specimens on histology and/or RUT. Serologic atrophy was determined by pepsinogen levels. Overall H. pylori infection rate was 72.5%. The proportions of moderate-to-marked atrophy/intestinal metaplasia at CGC (5.6/6.6%) were significantly lower than those at antrum (58.6/75.8%) and CLC (60.7/70.0%). Sensitivity of histology in detecting H. pylori was significantly higher at CGC than at antrum and CLC (84.8 vs 30.3 and 47.0%, respectively; p < .001). On RUT, detection at CGC also showed higher sensitivity than at antrum (77.3 vs 33.3%, p < .001). Specificities of all three biopsy sites were more than 90%. Regardless of serologic atrophy, CGC showed consistently higher sensitivities on histology and RUT. In patients with serologic atrophy, antral sensitivities were much lower than those of nonatrophic patients, 9.5 versus 40.0% on histology (p = .012) and 14.3 versus 42.2% on RUT (p = .025). CGC is the optimal biopsy site for H. pylori diagnosis in EMR patients with extensive atrophy. Antral biopsy should be avoided, especially in serologically atrophic patients.