Family history of cancer in first-degree relatives and risk of gastric cancer and its precursors in a Western population

Family history may inform risks of gastric cancer and preneoplastic lesions. We examined associations with history of cancer in first-degree relatives for 307 incident gastric cancer cases among 20,720 male smokers in a prospective study in Finland. Cox regression was used to calculate gastric cancer hazard ratios (HR) and 95% confidence intervals (95% CI). Logistic regression was used to estimate odds ratios (OR) and 95% CIs for low serum pepsinogen, a marker of gastric atrophy. Gastric cancer risk was associated with gastric cancer history in first-degree relatives overall (HR 1.56, 95% CI 1.15-2.12), in fathers (HR 1.67, 95% CI 1.09-2.55) and in siblings (HR 2.05, 95% CI 1.25-3.38). Associations were significant for noncardia (HR 1.83, 95% CI 1.30-2.57) but not cardia (HR 0.93, 95% CI 0.46-1.87) cancers, and marginal for both intestinal-(HR 1.53, 95% CI 0.92-2.55) and diffuse-type (HR 1.47, 95% CI 0.72-3.03) histologies. Family history of other cancer types was not associated with gastric cancer risk. Family history of gastric cancer was associated with low pepsinogen (OR 1.29, 95% CI 1.11-1.50). Family history of gastric cancer is strongly associated with specific subtypes of gastric cancer as well as with gastric atrophy, a risk factor for developing this malignancy.