Clinicopathological findings in patients with gastric adenocarcinoma with familial aggregation.

BACKGROUND/AIMS: The clinicopathological characteristics of gastric cancer (GC) with a positive family history of site-specific GC have not been well discussed. The aim of this study was to estimate the risk of familial aggregation of GC in a hospital-based case-control study and to analyze the clinicopathological characteristics of GC with familial aggregation of GC. METHODS: Our series was comprised of 926 histologically confirmed patients with GC (588 males and 338 females) and 2,052 non-cancer outpatients between 1985 and 1996. The odds ratios (ORs), as estimators of relative risks, together with the corresponding 95% confidence intervals (CIs) for a family history of GC and for a family history of other cancers were calculated. Moreover, the clinicopathological findings of patients with GC who had a GC family history were compared with those of patients with GC who had no GC family history. RESULTS: A positive family history of GC was associated with a statistically significant increase in the risk of GC (OR = 2.15; 95% CI = 1.77-2.63), while no association was observed between the risk of GC and a family history of other cancers (OR = 1.11; 95% CI = 0.91-1.36). The incidence of a multifocal occurrence of GCs was higher in patients with a family history of GC (19.4%) than in patients without a family history of GC (12%, p = 0.005). The risk (OR) of occurrence of multiple cancers in the stomach in patients who had a family history of GC was 1.77 (95% CI = 1.19-2.64). CONCLUSIONS: Our results suggest that a family history of GC seemed to be a risk factor for the development of GC. Further, a family history of GC was found to be associated with a multifocal occurrence of GC.