Survival Rate of Colorectal Cancer in Iran: A Systematic Review and Meta-Analysis

Abstract

Background: Different studies have been conducted to estimate the survival rate of colorectal cancer in Iran but<br />there is no overall estimate of the survival rate. The aim of this study was to calculate the pooled 1, 3, and 5-year survival<br />rate of the patients with colorectal cancer in Iran. Methods: To retrieve relevant studies, we conducted a systematic<br />search in Iranian databases, including Iran Medex, Magiran, SID, and international databases such as Medlin/PubMed,<br />Scopus, and Google scholar using “Colorectal Neoplasms" and “Survival Rate" as keywords up to December 1st, 2017.<br />We used random effect model to estimate pooled 1, 3, and 5-year survival rates of the patients with colorectal cancer<br />in Iran. To assess the heterogeneity, we used Chi-squared test at the 5 % significance level (p <0.05) and I2 Index. We<br />used meta-regression and subgroup analysis to find a potential source of heterogeneity. Results: After a systematic<br />search, 196 articles were found, of the 38 studies met the eligibility criteria and are included in our meta-analysis. The<br />pooled 1, 3, and 5-year survival rates in patient with colorectal cancer were 0.84 (95% CI: 0.81-0.87), 0.64 (95%CI:<br />0.59-0.70), and 0.54 (95%CI: 0.49-0.58) respectively. The 5-year survival rate in the subgroup of women was 0.5<br />(0.44-0.56) and in male subgroup was 0.44 (0.40-0.48). In a subgroup of the tumor site, the 5-year survival rate in colon<br />cancer was 0.6 (0.49-0.75) and rectum cancer was 0.54 (0.36-0.69). In multivariable models, there was a significant<br />association between years of study and 5-year survival rate as a source of heterogeneity (β = 18.9, P=0.01). Conclusion:<br />According to the results of this study, women had a better survival rate than men, and according to the tumor site, the<br />5-year survival rate in colon cancer was better than the rectum cancer.