Comparison of the short‐ and long‐term prognosis of early‐onset colorectal cancer compared with later‐onset colorectal cancer: A systematic review and meta‐analysis

BACKGROUND AND AIMS: The annual incidence of early‐onset colorectal cancer (EOCRC) is increasing at an alarming rate. The prognosis of EOCRC remains controversial, and whether the early onset is a risk factor for colorectal cancer remains unclear. METHODS: We searched four electronic bibliographic databases from database inception to April 25, 2022 for studies that included both early‐ and later‐onset patients and performed a prognostic analysis. Random‐effects models were used to summarize the prognostic information extracted by the investigators, including overall survival (OS), cancer‐special survival (CSS), and disease‐free survival (DFS). Network meta‐analysis (NMA) was used to compare patients' long‐term prognoses in different age subgroups. RESULTS: After 694 reports were screened, 13 studies were included in the final analysis, with a total of 448,781 CRC cases. In the meta‐analysis of the 5‐year OS, EOCRC had a better prognosis compared to LOCRC (hazard ratio [HR] 0.87, 95% confidence interval [CI], 0.74–0.99; relative risk [RR] 0.83, 95% CI, 0.78–0.89). No difference in prognosis was found between the two groups in terms of 5‐year CSS (RR 0.99, 95% CI, 0.93–1.05), 5‐year DFS (RR 0.90, 95% CI, 0.74–1.09), and short‐term OS. In the NMA, patients aged <30 years had the worst outcome (surface under the cumulative ranking curve [SUCRA], 15.8%) in 5‐year OS; consistent results were observed in the analysis of 5‐year CSS (<30 years, SUCRA 4.5%), but the difference was not statistically significant. CONCLUSION: Although patients with early‐onset CRC had better OS than those with later‐onset CRC, there was no difference in the CSS. Meanwhile, the trend for survival was worse in younger patients, especially in those ages 18–29 years. Thus, more attention should be paid to early diagnosis and treatment of EOCRC. SYSTEMATIC REVIEW AND META‐ANALYSIS REGISTRATION: The systematic review and Meta‐analysis protocol was registered with PROSPERO (registration number CRD42022334697).