Factors related to the participation and detection of lesions in colorectal cancer screening programme-based faecal immunochemical test.

Background: The overall aim of this study was to describe trends in participation rates and detection of lesions in a colorectal cancer (CRC) screening programme, during three rounds, using faecal immunochemical test (FIT). Methods: National registers were used to collect data on invitations for CRC screening in the Basque Country (Spain) from 2009 to 2014. Information about participation, age, gender and lesions in each round were collected. Results: A total of 961.533 individuals were included in the analysis; respectively, 584.950, 298.143 and 78.440 in the first, second and third rounds. The average participation rate was 68.4% (66.8, 70.4 and 72.3%, respectively by round; P < 0.001) and the positivity rate was 6.3% (7, 5.5 and 5.4%, respectively by round; P < 0.001). The participation rate increased significantly with age and was found to be higher in women versus men. A total of 15.144 advanced adenomas and 2.131 CRCs were diagnosed, leading to a detection rate of 23.9 and 3.4‰, respectively. Regarding gender, men had the highest rates in all periods and rounds. The detection rate of advanced neoplasia was lower in the regular when compared with irregular paricipants. Conclusions: In a CRC screening, this organization obtained high FIT participation rates. Older participants and women were associated with a higher participation. The detection rate of lesions was higher in men, independent on age and round.

[Lesions detected in a colorectal cancer screening program in the Basque Country: first round (2009-2011)]. / Lesiones detectadas en el programa de cribado de cáncer colorrectal en el País Vasco: primera ronda 2009-2011.

UNLABELLED: Colorectal cancer (CRC) is a major public health problem due to its incidence and mortality. In May 2008, the Basque Country approved the implementation of a population-based colorectal cancer screening program, using the immunochemical fecal occult blood test (FOBT), in persons aged 50-69 years. Patients with a positive result were invited to undergo colonoscopy with sedation. OBJECTIVE: To describe the main results of the first round of the CRC screening program with FOBT (2009-2011) in terms of the detection rates and positive predictive value (PPV). METHOD: Retrospective study of participation rates and colonoscopic findings in persons with a positive FOBT result. RESULTS: Invitations to attend screening were sent to 230.505 persons. A total of 148.249 FOBT tests were processed. The mean participation rate was 64.3% (95% CI: 64.1-64.5) and was higher in women than in men. The FOBT test was positive in 6.7% (95% CI: 6.6-6.8). Positive results were more frequent in men. Among persons with a positive result, colonoscopy was performed in 93.1%. There were significant differences between women and men in the detection rate of high-risk adenomas (OR: 0,45 95% CI 0,41-0,49), which, as with CRC (OR: 0,80 95% CI 0,66-0,96), were more frequent in men. The PPV for adenoma of any type was significantly higher in men (72.4 95% CI, 71.2-73.5) than in women (48.8% 95% CI 47.2-50.5), with differences by age group and type of adenoma. CONCLUSIONS: Participation rates and detection of advanced lesions and CRC were high. Because men have a higher risk of developing CRC, efforts should be made to increase their participation. The impact of the CRC screening program should be evaluated in the medium to long term.