First-degree relatives of colorectal cancer patients are likely to show advanced colorectal neoplasia despite a negative fecal immunochemical test.

BACKGROUND/AIMS: Fecal immunochemical test (FIT) is an integral component of most colorectal cancer (CRC) screening programs. However, little is known about clinical risk factors associated with advanced colorectal neoplasia (CRN) despite negative FIT results. The aim of this study was to determine the clinical predictors of advanced CRN despite negative FIT results.

METHODS

We performed FITs for asymptomatic subjects ≥50 years from January 2009 to December 2010. Patients who underwent colonoscopy for a medical check-up, despite a negative FIT result, were included to evaluate the clinical predictors of advanced CRN based on colonoscopy.

RESULTS

During the study period, 373 subjects underwent screening colonoscopy despite their negative FIT results. Among those 373 subjects, 356 (95.4%) did not show any advanced CRNs; however, 17 (4.6%) subjects showed advanced CRNs on their colonoscopies despite negative FIT results. Being a first-degree relative of a CRC patient was significantly associated with advanced CRNs in univariate analysis (p = 0.031). According to multivariate logistic regression analysis, being a first-degree relative of a CRC patient was a significant predictor of advanced CRNs despite negative FIT results (OR 7.33; 95% CI, 0.53-35.08; p = 0.013).

CONCLUSION

First-degree relatives of CRC patients are likely to show advanced CRNs despite a negative FIT.