Survival Outcomes of Patients With Colorectal Cancer After Primary Surgery: A Population-Based Study in Hainan, China.

BACKGROUND

Colorectal cancer (CRC) is a major public health burden in Hainan Province due to its high incidence and mortality, yet region-specific prognostic data are lacking. This study evaluates prognostic factors in postsurgical CRC patients to guide localized prevention and treatment.

METHODS

We conducted a retrospective cohort study of 265 patients undergoing first-time surgery for CRC between January 2015 and December 2021. Kaplan-Meier estimator and log-rank tests were performed to analyze the overall survival rates of CRC patients. Cox proportional hazards regression and the SHAP method were performed to determine the prognostic factors of CRC.

RESULTS

The study included 265 patients (mean age 63 ± 12.99 years), with 171 survivors (64.5%) and 94 deaths (35.5%). The 1-, 3- and 5-year overall survival rates of CRC patients were 93.0%, 82.1%, and 73.9%, respectively, from 2015 to 2021. In multivariable analysis, factors associated with increased mortality risk included advanced age (per 1 year increase: HR = 1.043, 95% CI: 1.018-1.069, p = 0.001), TNM stage III (HR = 11.46, 95% CI: 2.611-50.31, p = 0.001) and stage IV (HR = 15.06, 95% CI: 3.131-72.46, p = 0.001), increased tumor size (per 1 cm increase: HR = 1.267, 95% CI: 1.058-1.519, p = 0.01), positive vascular infiltration (HR = 2.399, 95% CI: 1.162-4.951, p = 0.018), elevated CEA levels (per 1 ng/mL increase: HR = 1.035, 95% CI: 1.012-1.059, p = 0.003), and increased CA125 levels (per 1 U/mL increase: HR = 1.013, 95% CI: 1.003-1.024, p = 0.014), while normal-weight (HR = 0.385, 95% CI: 0.168-0.880, p = 0.024) was associated with a better survival. No association was found between the expression of MSH2, MDR1, and GSTπ and the survival of the patients. The SHAP beeswarm plot highlighted TNM stage and age as the primary contributors to the model's predictions.

CONCLUSION

Increased age, advanced TNM stage, larger tumor size, vascular invasion, and elevated CEA/CA125 were linked to poorer CRC prognosis, while normal BMI was protective. Further prospective studies are needed for validation.