Survival Analysis of Patients with Colorectal Cancer Undergoing Combined Treatment: A Retrospective Cohort Study

Background: If colorectal cancer (CRC) is diagnosed in the early stages, the patients will have higher survival rates. Although some other factors might affect the survival rate, the type of treatment available based on existing health and therapeutic facilities is extremely important as well. Accordingly, this study aimed to explore the best type of treatment for CRC patients. Study Design: This study employed a retrospective population-based cohort design. Methods: The data of 335 patients with CRC in Kurdistan province were collected through a population -based cancer registry system from March 1, 2009 to 2014. Demographic and clinical-pathologic data of the patients were gathered through their medical records, pathology reports, and reference to patients' homes. The survival rate was calculated using the Kaplan-Meier curve, log-rank test, and univariate and multivariate Cox regression. The data were analyzed using Stata 14 software. Results: In this study, the mean age +/- standard deviation at diagnosis was 61.7 +/- 1.05 in men and 60.5 +/- 1.12 in women, respectively, and 203 (60.5%) patients were males. There was less mortality rate among the patients who received both surgical and chemotherapy treatments compared to those who did not receive any treatment (Hazard ratio [HR] = 0.57, 95% CI: 0.24-0.93). Conclusion: When CRC patients are treated using both surgical and chemotherapy treatments, they will exhibit a higher survival rate. Therefore, it is suggested to use both treatments for CRC patients.