Do we need colonoscopy in patients with gastric adenomas? The risk of colorectal adenoma in patients with gastric adenomas.

BACKGROUND

Gastric polyps are found frequently in various colonic polyposis syndromes. Genetic alterations of several genes occur in gastric adenomas and colorectal adenomas. However, it is unknown whether patients with gastric adenomas are at higher risk for colorectal adenomas.

OBJECTIVE

To investigate the prevalence rate of colorectal adenoma in patients with gastric adenomas and to determine the association between the presence of gastric adenomas and synchronous colorectal adenomas.

DESIGN

A retrospective, cross-sectional, case-control study.

SETTING

Single center: Center for Health Promotion of Samsung Medical Center.

PATIENTS

This study involved 87 patients with gastric adenomas and 174 sex-matched and age-matched controls among 19,019 participants who underwent EGD and colonoscopy simultaneously or within 6 months of each other from January 2001 to December 2008 at the Center for Health Promotion of Samsung Medical Center.

INTERVENTION

EGD and colonoscopy.

MAIN OUTCOME MEASUREMENTS

The prevalence rate of colorectal adenoma in patients with gastric adenomas.

RESULTS

The 87 gastric adenoma patients included 72 men and 15 women. Colorectal adenomas were identified in 42 (48.3%) of 87 cases and in 58 (33.3%) of 174 controls (P = .022). The prevalence of colorectal adenoma was significantly higher in the gastric adenoma group than in the control group. The mean size and number of colorectal adenomas were not significantly different between the two groups. The majority of colorectal adenomas were located in distal colonic segments in the gastric adenoma group in contrast with proximal colonic segments in the control group. Multivariate logistic regression analysis revealed that independent risk factors for colorectal adenoma were the presence of gastric adenomas (odds ratio [OR], .915; 95% confidence interval [CI], 1.044-3.513) and increasing age over 55 years (OR, 2.943; 95% CI, 1.558-5.560).

LIMITATIONS

Lack of data on previous colorectal adenomas and possible confounding factors such as hyperlipidemia or diabetes mellitus.

CONCLUSION

The risk of colorectal adenoma increases significantly in patients with gastric adenomas and in patients over age 55. A screening colonoscopy may be necessary for patients with gastric adenomas to detect colorectal adenomas.