Survival trends for left and right sided colon cancer using population‐based SEER database: A forty‐five‐year analysis from 1975 to 2019

Abstract Background Survival differences between left‐sided colon cancer (LSCC) and right‐sided colon cancer (RSCC) has been previously reported with mixed results, with various study periods not accounting for other causes of mortality. Purpose We sought to assess the trends in colon cancer cause‐ specific survival (CSS) and overall survival (OS) based on sidedness. Method Fine‐Gray competing risk and Cox models were used to analyze Surveillance, Epidemiology, and End Results (SEER) population‐based cohort from 1975 to 2019. Various interval periods were identified based on the timeline of clinical adoption of modern chemotherapy (1975–1989, interval period A; 1990–2004, B; and 2005–2019, C). Results Of the 227,637 patients, 50.1% were female and 46.2% were RSCC. RSCC was more common for African Americans (51.5%), older patients (age ≥65; 51.4%), females (50.4%), while LSCC was more common among Whites (53.1%; p