Which genotype of Helicobacter pylori-cagA or cagE-Is better associated with gastric Cancer risk? Lessons from an extremely high-risk area in Iran.

The association of the H. pylori cagA- /cagE-positive genotypes with the risk of gastric cancer (GC) in Ardabil-a high-risk area in North-West Iran-was assessed. Genotyping was performed in DNA from fresh gastric biopsies (N = 218). Occurrence of H. pylori infection was 85.32% (186/218). The total frequency of the cagA+vs. cagA-, cagE+vs. cagE-, cagA+/cagE-vs. AGCs (all genotype combinations), cagA-/cagE+vs. AGCs, cagA-/cagE-vs. AGCs, cagA+/cagE+vs. AGCs, cagA+/cagE-vs. cagA-/cagE+, and cagA+/cagE+vs. cagA-/cagE- genotypes was 102/186 (54.8%), 89/186 (47.8%), 38/186 (20.4%), 25/186 (13.4), 59/186 (31.7%), 64/186 (34.4%), 38/63 (38.63%), and 64/123 (52.0%), respectively. The cagE+vs. cagE- (59.6% (65/109) in GC vs. 31.2% (24/77) in non-atrophic gastritis, NAG) and the cagA+/cagE+vs. cagA-/cagE- genotypes (66.7% (40/60) in GC vs. 38.1% (24/63) in NAG) showed an increased association with the risk of GC in Ardabil (odds ratio [OR] = 3.262, 95% confidence interval [CI]: 1.763-6.038, p = .0001 and OR = 3.250; 95% CI: 1.552-6.808, p = .002, respectively). We propose that the H. pylori cagE+ but not cagA+ genotype significantly increased the risk of GC in this extremely high-risk population. Therefore, it may play a significant role in determining H. pylori-related clinical outcome.