Long-term outcomes following the resection of screen-detected right-sided colon cancer

Background: The relative outcomes following the resection of screen-detected right-sided colon cancer compared to symptomatic cases are unknown. In this study, short and long-term outcomes after right-sided colectomy in screen-detected colon cancer are compared with symptomatic cases, both emergency and elective. Methods: A prospective observational cohort study of patients, including both screen-detected and symptomatic patients (elective and emergency resections), undergoing right-sided colectomy for colon cancer (2010-2020) in a tertiary care unit was conducted. Each patient was followed up for long-term recurrence and survival. Results: A total of 909 patients (median age, 70; IQR, 58-82; male, 52%) were included (151 patients (16.6%) screen-detected; 598 (65.8%) elective and 160 (17.6%) emergency). Screen-detected patients were more likely to have T1 or T2 lesions compared to elective and emergency groups (T1: 14.6% vs. 3.8% vs. 0.6% p < 0.001; T2: 16.6% vs. 8.9% vs. 3.1% p < 0.001), but were less likely to have T3 or T4 lesions (p < 0.001), respectively. Rates of N0 were higher in the screen-detected group (68.9% vs. 63.5% vs. 41.9%, respectively; p < 0.001). 98% of the screen-detected group achieved R0 resection compared to 93.3% of elective and 79.4% of emergency patients (p < 0.001). At 5-years following resection, overall survival for the screen-detected, elective, and emergency groups were 85.4%, 75.4%, and 53.1%, respectively (p < 0.001). Recurrence at 5-year post-resection were 8%, 15.1%, and 22.5% for the screen-detected, elective, and emergency groups, respectively (p < 0.001). Discussion: When considering right-sided colon cancer alone, screen-detected cancers have a lower long-term recurrence rate, lower rates of postoperative complication, and superior survival compared to symptomatic groups following resection.