Risk of gastric cancer in patients with non-surgically treated peptic ulcer.

We followed up 2072 patients with unoperated gastric and duodenal ulcer, diagnosed from 1963 to 1975, and evaluated the risk of development of gastric cancer. During the follow-up period of 9-23 years 38 patients had a gastric cancer or died of gastric cancer. The number of gastric cancers in patients with duodenal ulcer (observed/expected = 3:12) was statistically low (p less than 0.01) compared with the number expected from the sex- and age-matched general population. On the other hand, the number of patients with gastric ulcer and the number of those with both gastric and duodenal ulcers was 29 and 6, neither of which differed significantly from the expected occurrence. These results suggest that in peptic ulcer patients the risk of developing gastric cancer is equal to or low compared with that of the general population.