[Clinical usefulness of fecal occult blood test as a screening method for asymptomatic patients with colon polyps].

Background/aims: Detection of asymptomatic benign colon polyp is increasing because colonoscopy is widely used as a screening and diagnostic method. Fecal occult blood test is usually performed for the selection of patients requiring colonoscopy as well as mass screening for colon cancer. The aim of this study was to investigate the usefulness of fecal occult blood test performed prior to colonoscopy as a screening method of benign colon polyps.

Methods: Clinical characteristics of patients with polyps were evaluated according to the fecal occult blood test results in patients who underwent one-day fecal occult blood test and colonoscopic polypectomies from May 2003 to October 2004, retrospectively.

Results: A total of 942 colonoscopic polypectomies in 288 patients were evaluated. Fecal occult blood tests were positive only in 32 patients (11.1%). In univariate analysis, there was a significant difference in polyp size (p=0.02) and location (p=0.03) according to the presence of positive fecal occult blood tests. In addition, age of the patient (p=0.046), polyp size (mean, p=0.04; largest, p<0.01) and the number of polyps (p=0.045) were significantly different. However, in multivariate analysis, only polyp size larger than 20 mm was significantly related with positive fecal occult blood test with estimated odds ratio of 4.71.

Conclusions: Fecal occult blood test has limitations as a screening test in asymptomatic patients with colon polyps, except for colon polyps larger than 20 mm in size.