Epidemiology and survival analysis of colorectal cancer and its related factors

Colorectal cancer (CRC) is one of important malignancies in the world and is the most frequent gastro-intestinal cancer. There is limited data on epidemiologic features and related factors of this malignancy in Iran. The aim of this study was to investigate the epidemiologic features and survival analysis of colorectal cancer and some of its related factors in Iran.

This case series descriptive study was performed on 241 colorectal cancer patients who referred to a hospital in Tehran from 2004 to 2009. Data collection was based on medical records and phone calls. Survival analyses were constructed using the Kaplan-Meier and Cox-regression methods in order to determine the survival and compare the survival rates in subgroups. Data was analyzed by SPSS 15 software.

Mean age of participants was 59.7 ± 14.7 years, 22.4% were smoker and 24.5% had family history of CRC. Rectum cancer was the most common anatomic site of CRC and cancer grading reported well differentiation in most cases. 83.8% of study units were alive till the end of study. The mean survival time was 56.5 ± 1.9 months. The lowest and highest mean survival time were 47.7±5.8 for secum cancer and 61.1±3.2 for non smokers respectively. The highest odds ratio of survival was 2.12 (95% CI: 0.28-15.87) and belonged to patients with rectum cancer.

The mean survival time for CRC is about 5 years and depends on some risk factors. Evaluation of these risk factors seems to be necessary in lower ages.