Application of Inverse Entezar Weibull in Identification of Influential Factors on Survival of patients with Colorectal Cancer

Background: Colorectal cancer is the third most common cancer in the world and the second leading cause of death among cancers. In recent decades there have been significant changes in the incidence of this cancer in Asian countries. Unlike the declining mortality rates in Europe and North America, this rate is rising in Iran. Therefore the survival of patients with this disease is important. The aim of this study was to determine the factors affecting the survival time of colorectal cancer patients.Methods: ۲۳۵ patients with colorectal cancer referred to the gastroenterology center of Taleghani Hospital in Tehran from ۲۰۰۴ to ۲۰۱۴, were analyzed in this study. Inverse Entezar Weibull (IEW) distribution was used to identify the factors affecting the survival time. Statistical analysis was performed in R at the significant level (p<۰.۰۵).Results: (۲۶.۸%) of the ۶۳ patients died due to colorectal cancer. One-year, five-year and eight-year survival was ۹۰.۲%, ۷۶.۶% and ۷۴.۲%, respectively. The median survival rate for patients with colon cancer was ۲۶ and for patients with rectal cancer was ۱۷±۷.۸. Age at diagnosis and BMI were identified as factors that affects the survival time of patients with colorectal cancer.Conclusions: This study showed that age at diagnosis and BMI were influential factors in survival of colorectal cancer patients.

کلیدواژه ها:

colorectal cancer ، survival analysis ، Inverse Entezar Weibull distribution ، survival time