Effects of Attendance to an Organized Fecal Immunochemical Test Screening Program on the Risk of Colorectal Cancer: An Observational Cohort Study
Authors: Flavia Baldacchini, Lauro Bucchi, Orietta Giuliani, Silvia Mancini, Alessandra Ravaioli, Rosa Vattiato, Federica Zamagni, Paolo Giorgi Rossi, Lucia Mangone, Cinzia Campari, Romano Sassatelli, Paolo Trande, Pasqualina Esposito, Federica Rossi, Giuliano Carrozzi, Omero Triossi, Carlo Fabbri, Enrico Strocchi, Mauro Giovanardi, Debora Canuti, Priscilla Sassoli de Bianchi, Stefano Ferretti, Fabio Falcini, Alba Carola Finarelli, Patrizia Landi, Francesca Mezzetti, Carlo Naldoni, Priscilla Sassoli de Bianchi, Stefano Ferretti, Flavia Baldacchini, Lauro Bucchi, Orietta Giuliani, Silvia Mancini, Alessandra Ravaioli, Federica Zamagni, Rosa Vattiato, Chiara Balducci, Benedetta Vitali, Fabio Falcini, Giovanni Aragona, Giorgio Chiaranda, Francesca Penini, Pietro Seghini, Cristian Dalla Fiora, Claudio Fattibene, Fabio Maradini, Paolo Orsi, Giada Maria Benedetta Giannino, Maria Michiara, Paolo Giorgi Rossi, Lucia Mangone, Cinzia Campari, Luisa Paterlini, Romano Sassatelli, Giuliano Carrozzi, De Girolamo Gianfranco, Pasqualina Esposito, Federica Rossi, Paolo Trande, Simona Viani, Claudia Cirilli, Carmen Bazzani, Franco Bazzoli, Vincenzo Cennamo, Chiara Giansante, Giovanna Gualandi, Marilena Manfredi, Francesca Mezzetti, Adriana Pasquini, Licia Caprara, Margherita De Lillo, Aldo De Togni, Caterina Palmonari, Daniela Pasquali, Giorgio Zoli, Serena Dal Re, Chiara Petrini, Monica Serafini, Omero Triossi, Mara Gallinucci, Claudia Imolesi, Mauro Palazzi, Debora Canuti, Coralba Casale, Mauro Giovanardi, Daniele Trombetti
Journal: Clinical Gastroenterology and Hepatology (2022)

Background & AimsThis cohort study compared colorectal cancer (CRC) incidence and mortality between people who participated in an Italian regional biennial fecal immunochemical test (FIT) screening program and people who did not.MethodsThe program started in 2005. The target population included over 1,000,000 people aged 50 to 69 years. The FIT was a one-sample OC-Sensor (Eiken Chemical Co, Tokyo, Japan) (cutoff, ≥20 μg hemoglobin/g feces). The average annual response rate to invitation was 51.4%. The records of people invited up to June 2016 were extracted from the screening data warehouse. Attenders were subjects who responded to the first 2 invitations or to the single invitation sent them before they became ineligible. Non-attenders were subjects who did not respond to any of these invitations. The records were linked with the regional CRC registry. People registered up to December 2016 were identified. Self-selection-adjusted incidence rate ratios (IRRs) and incidence-based CRC mortality rate ratios (MRRs) for attenders to non-attenders, with 95% confidence intervals (CIs), were calculated.ResultsThe cohort generated 2,622,131 man-years and 2,887,845 woman-years at risk with 4490 and 3309 CRC cases, respectively. The cohort of attenders was associated with an IRR of 0.65 (95% CI, 0.61–0.69) for men, 0.75 (95% CI, 0.70–0.80) for women and 0.69 (95% CI, 0.66–0.72) for both sexes combined. The self-selection-adjusted IRR was 0.67 (95% CI, 0.62–0.72) for men and 0.79 (95% CI, 0.72–0.88) for women. The IRR for stage I, II, III, and IV CRC was 1.35 (95% CI, 1.20–1.50), 0.61 (95% CI, 0.53–0.69), 0.60 (95% CI, 0.53–0.68) and 0.28 (95% CI, 0.24–0.32) for men and 1.64 (95% CI, 1.43–1.89), 0.60 (95% CI, 0.52–0.69), 0.73 (95% CI, 0.63–0.85) and 0.35 (95% CI, 0.30–0.42) for women. The overall incidence-based CRC MRR was 0.32 (95% CI, 0.28–0.37) for men, 0.40 (95% CI, 0.34–0.47) for women and 0.35 (95% CI, 0.31–0.39) for both sexes combined. The adjusted MRR was 0.35 (95% CI, 0.29–0.41) for men and 0.46 (95% CI, 0.37–0.58) for women.ConclusionsAttendance to a FIT screening program is associated with a CRC incidence reduction of 33% among men and 21% among women, and a CRC mortality reduction of 65% and 54%, respectively. This cohort study compared colorectal cancer (CRC) incidence and mortality between people who participated in an Italian regional biennial fecal immunochemical test (FIT) screening program and people who did not. The program started in 2005. The target population included over 1,000,000 people aged 50 to 69 years. The FIT was a one-sample OC-Sensor (Eiken Chemical Co, Tokyo, Japan) (cutoff, ≥20 μg hemoglobin/g feces). The average annual response rate to invitation was 51.4%. The records of people invited up to June 2016 were extracted from the screening data warehouse. Attenders were subjects who responded to the first 2 invitations or to the single invitation sent them before they became ineligible. Non-attenders were subjects who did not respond to any of these invitations. The records were linked with the regional CRC registry. People registered up to December 2016 were identified. Self-selection-adjusted incidence rate ratios (IRRs) and incidence-based CRC mortality rate ratios (MRRs) for attenders to non-attenders, with 95% confidence intervals (CIs), were calculated. The cohort generated 2,622,131 man-years and 2,887,845 woman-years at risk with 4490 and 3309 CRC cases, respectively. The cohort of attenders was associated with an IRR of 0.65 (95% CI, 0.61–0.69) for men, 0.75 (95% CI, 0.70–0.80) for women and 0.69 (95% CI, 0.66–0.72) for both sexes combined. The self-selection-adjusted IRR was 0.67 (95% CI, 0.62–0.72) for men and 0.79 (95% CI, 0.72–0.88) for women. The IRR for stage I, II, III, and IV CRC was 1.35 (95% CI, 1.20–1.50), 0.61 (95% CI, 0.53–0.69), 0.60 (95% CI, 0.53–0.68) and 0.28 (95% CI, 0.24–0.32) for men and 1.64 (95% CI, 1.43–1.89), 0.60 (95% CI, 0.52–0.69), 0.73 (95% CI, 0.63–0.85) and 0.35 (95% CI, 0.30–0.42) for women. The overall incidence-based CRC MRR was 0.32 (95% CI, 0.28–0.37) for men, 0.40 (95% CI, 0.34–0.47) for women and 0.35 (95% CI, 0.31–0.39) for both sexes combined. The adjusted MRR was 0.35 (95% CI, 0.29–0.41) for men and 0.46 (95% CI, 0.37–0.58) for women. Attendance to a FIT screening program is associated with a CRC incidence reduction of 33% among men and 21% among women, and a CRC mortality reduction of 65% and 54%, respectively.