Repeated screening with fecal immunochemical tests reduced the incidence of colorectal cancers in Saga, Japan.

BACKGROUND/AIMS: Screening with fecal occult blood test has reduced mortality from colorectal cancer (CRC), with fecal immunochemical tests (FIT) widely utilized for CRC screening in Japan. To evaluate the importance of repeated FIT screening, the incidence of CRC was compared in patients undergoing initial and repeated screening. METHODOLOGY: Participants aged ≥40 years in Saga, Japan, were invited to undergo a 2-day FIT. FIT positive subjects were verified by colonoscopy to evaluate the CRC incidence rates. RESULTS: From 2005 to 2007, 55,595 individuals were invited to undergo CRC screening, including 47,168 undergoing repeated and 8,427 undergoing initial screening. Of the 5,832 FIT-positive subjects, 4,615 were assessed by colonoscopy, with 114 diagnosed as having CRC. Of these 114 patients, 67 had early and 47 had advanced CRC. The risk of CRC was 63% lower in the repeated than in the initial screening group (p<0.0001). Of the 67 patients with early CRC, 42 underwent endoscopic resection, with the rate significantly higher in the repeated than in the initial screening group (p = 0.01). Overall survival was longer in screened subjects than in those who visited hospitals with clinical symptoms. CONCLUSIONS: Repeated CRC screening with FIT reduced the incidence of CRC in Saga, Japan.