Abstract
BACKGROUND: Early onset Colorectal Cancer (EOCRC), defined as those diagnosed under the age of 50, has been increasing rapidly since 1970. UK data on EOCRC are currently limited and better understanding of the condition is needed. MATERIALS AND METHODS: A single-center retrospective study of patients with EOCRC treated over 9 years (2013-2021) at a large UK cancer center was performed. Clinicopathological features, risk factors, molecular drivers, treatment, and survival were analyzed. RESULTS: In total, 203 patients were included. A significant increase in cases was reported from 2018-2019 (n = 33) to 2020-2021 (n = 118). Sporadic EOCRC accounted for 70% of cases and left-sided tumors represented 70.9% (n = 144). Median duration of symptoms was 3 months, while 52.7% of the patients had de-novo metastatic disease. Progression-free survival after first-line chemotherapy was 6 months (95% CI, 4.85-7.15) and median overall survival (OS) was 38 months (95% CI, 32.86-43.14). In the advanced setting, left-sided primary tumors were associated with a median OS benefit of 14 months over right-sided primaries (28 vs 14 months, P = .009). Finally, primary tumor resection was associated with median OS benefit of 21 months compared with in situ tumors (38 vs 17 months, P < .001). CONCLUSIONS: The incidence of EOCRC is increasing, and survival outcomes remain modest. Raising public awareness and lowering the age for colorectal cancer screening are directions that could improve EOCRC clinical outcomes. There is also a need for large prospective studies to improve the understanding of the nature of EOCRC and the best therapeutic approaches.