Inverse Entezar Weibull and Its Application in Identification of Influential Factors on the Survival of Patients with Blood Cancers

Background:Blood cancer is a disease with a high burden level and a mortality rate of 2.8% which has a growing trend in Iran. For this reason, it is important to study the survival ratio of patients who were afflicted with this disease. The present study was conducted to determine the factors affecting the survival time of patients with various types of blood cancers.Objectives:This is a historical cohort study that examines the survival of patients with blood cancer who received bone marrow transplants in the presence of some explanatory variables.Methods:This descriptiveanalytical study was performed on data extracted from files in the bone marrow transplant department, Taleghani Hospital, Tehran, Iran which is affiliated with Shahid Beheshti University of Medical Sciences. Patients who were candidates for a bone marrow transplant from all over the country (from 2007 to 2016) with different types of complaints were considered as the subjects of this study. Inverse Entezar Weibull model was used to analyze the survival time and investigate the factors affecting the survival of patients.Results:Of 99 patients, 20.1% died of a type of blood cancer. Oneyear, fiveyear and eightyear survival of patients were 90.2%, 76.6%, and 74.2%, respectively. Age at diagnosis time, number of relapses before bone marrow transplant, and the type of diagnosis were identified as factors affecting the survival time of patients with different types of blood cancer.Conclusions:This study showed that age factor at the time of diagnosis, the number of relapses before the bone marrow transplant, and the type of diagnosis were effective factors in the survival of patients with blood cancer.