In 50 Helicobacter pylori-infected gastric carcinoma patients the corpus gastritis was significantly higher than in matched H. pylori-positive control subjects (P < 0.01). Atrophy and intestinal metaplasia (IM) occurred significantly more often in the antrum of carcinoma patients (P < 0.01). The odds ratio for gastric carcinoma was 8.85 for high-grade corpus gastritis and 8.04 when atrophy in the antrum was present.