Abstract
BACKGROUND: This study investigated the overall survival (OS) at 1-year, 3-years, and 5-years after colorectal cancer (CRC) diagnosis and examined the prognostic factors of mortality among patients with CRC in Vietnam's central region. METHODS: This ambidirectional cohort study included patients newly diagnosed with CRC at a tertiary hospital in Vietnam's central region between 2013 and 2019. Survival duration was calculated from the surgery date or the first day of CRC-specific treatment until the date of death or the study's end date, July 31, 2020. Kaplan-Meier methods and log-rank test were used to estimate and compare the OS between the subgroups, respectively. The Cox proportional-hazards (PH) regression analysis was applied to estimate the magnitude of the effects between prognostic factors and outcome. RESULTS: The median follow-up was 24 months (interquartile range: 13-43 months). The OS rate dropped significantly to 84.7%, 56.19%, and 45.01% at 1-year, 3-years, and 5-years after diagnosis, respectively. The median OS was 48.59 months (39.34 -57.93 months) for the rectum and colon cases. In the multivariate analysis, a higher mortality risk was observed in patients with an advanced-stage CRC (HRadj, 3.04; 95% confidence interval [CI], 1.79-5.18), who were underweight (<18.5 kg/m2; HRadj, 1.65; 95%CI, 1.03-2.65), and had elevated preoperative carcinoembryonic antigen (CEA) level (>5.0 ng/mL; HRadj, 1.63; 95%CI, 1.03-2.59). Additionally, younger patients (<50 years) had a poorer OS than the middle-aged group (60-69 years). CONCLUSION: Our findings indicate that <50% of Vietnamese patients with CRC survive until 5-years after diagnosis. Several individual factors that contribute to the poor OS of patients with CRC, including young age, underweight, and elevated preoperative CEA level, should be evaluated and managed. Early diagnoses through active routine examination of or screening programs for high-risk groups should be prioritized.