A Combination of Fecal Immunochemical Test Results and Iron Deficiency Anemia for Detection of Advanced Colorectal Neoplasia in Asymptomatic Men

PURPOSE A substantial proportion of patients with colorectal cancer (CRC) present with iron deficiency anemia (IDA), and fecal immunochemical test (FIT) has proven to be an effective method for detecting the majority of CRC cases. A combination strategy of FIT results and IDA may be useful for risk stratification for detecting advanced colorectal neoplasia (ACRN). We compared the prevalence of ACRN among four groups stratified by FIT results and the presence of IDA. MATERIALS AND METHODS A cross-sectional study was performed on asymptomatic male participants who underwent both FIT and colonoscopy between 2010 and 2014 as part of a comprehensive health screening program in Korea. RESULTS Of 17236 participants, 522 (3.0%) showed positive FIT results and 26 (0.2%) had IDA. The mean age of the study participants was 40.8 years. The participants were classified into four groups: positive FIT result/IDA (G1, n=7), positive FIT result/no IDA (G2, n=515), negative FIT result/IDA (G3, n=19), and negative FIT result/no IDA (G4, n=16695). The prevalences of ACRN in G1, G2, G3, and G4 were 28.6, 13.4, 5.3, and 1.5%, respectively (p<0.001) and those of CRC were 28.6, 1.6, 0.0, and 0.01%, respectively (p<0.001). Subjects with positive FIT results and IDA had an increased risk of ACRN and CRC in both group aged <50 and ≥50 years. CONCLUSION Subjects with positive FIT results and IDA had an increased risk of ACRN. Our results suggest that a combination strategy of FIT and IDA may be helpful in selecting and prioritizing asymptomatic men for colonoscopy.