Endoscopic resection vs. endoscopic resection plus chemoradiation for T1 stage colorectal cancer: a real-world retrospective cohort study

Early-stage colorectal cancer (CRC) patients treated with either endoscopic resection (ER) alone or combined ER with chemoradiotherapy (CRT) have unknown survival rates. A national descriptive epidemiological study was conducted to compare the long-term survival of patients with T1 stage CRC with or without the two different treatment options.Our study identified the records of patients with T1-stage CRC between 2010 and 2018 by searching the Surveillance, Epidemiology, and End Results (SEER) database. Long-term survival was compared using Kaplan-Meier methods and Cox proportional hazard models based on patient demographic and cancer parameters.After propensity score matching (PSM), 825 T1-stage CRC patients were finally enrolled in this study, with 718 patients treated with ER and 107 patients treated with ER + CRT. The overall survival (OS) and cancer specific survival (CSS) rates were similar between the two treatment options (OS: P=0.47; CSS: P=0.28). According to subgroup analysis, older patients and patients with rectal tumor locations exhibited significantly higher OS and CSS rates in the ER + CRT group than in the ER group (OS: P<0.0001; CSS: P<0.0001).The findings from the SEER database showed that OS and CSS rates were similar between the ER and ER + CRT treated groups. Older patients and patients with rectal cancer benefited the most from ER + CRT treatment.