Hawaiian Japanese men (n = 432) who had undergone subtotal gastrectomy for peptic ulcers before 1971-1975 were followed up for detection of cancer development. They showed a significant increase in colon cancer risk (P = 0.008) and lung cancer risk (P = 0.002) compared with 6161 nongastrectomized men. The association with lung cancer persisted after adjustment for cigarette use (P = 0.03). Alcohol consumption was associated with colonic cancer in this cohort, and gastrectomized men consumed more alcohol than nongastrectomized men; however, the association of gastrectomy with colon cancer persisted after adjustment for alcohol use (P = 0.02). Gastrectomized men were lighter and had lower serum lipid levels than controls, suggesting that undernutrition might favor the development of some cancers. The type of gastroenteric anastomosis did not influence the cancer risk level in the colon or lung.