Author/Authors :
Azizmohammad Looha, Mehdi Department of Biostatistics - Faculty of Paramedical Sciences - Shahid Beheshti University of Medical Sciences, Tehran, Iran , Zarean, Elaheh Modeling in Health Research Center - School of Public Health - Department of Epidemiology and Biostatistics - Shahrekord University of Medical Sciences, Shahrekord, Iran , Pourhoseingholi, Mohamad Amin Gastroenterology and Liver Diseases Research Center - Research Institute for Gastroenterology and Liver Diseases - Shahid Beheshti University of Medical Sciences, Tehran, Iran , Hosseini, Vahid Colorectal Research Center - Shiraz University of Medical Sciences, Shiraz, Iran , Azimi, Tara School of Public Health - University of Alberta, Edmonton, Alberta, Canada , Khodakarim, Soheila Department of Epidemiology - School of Public Health - School of Paramedical Science - Shahid Beheshti University of Medical Sciences, Tehran, Iran
Abstract :
Background: Colorectal cancer (CRC) is a heterogeneous disease that occurs in different parts of the gastrointestinal system.
Objectives: This study aimed at analyzing the effects of risk factorsonsurvivalandcure fraction of patients withCRCin a population
of Iranian patients, using parametric non-mixture cure rate model.
Methods: This retrospective cohort study was conducted at Shiraz University of Medical Sciences on 512 patients with CRC. Patients
were followed-up for 8 years, fromJanuary2009until February 2017. Stepwise selectionandparametric non-mixture cure ratemodel
were used tofindthe risk factors of survival in patients with CRC. Akaike information criteriawasused to identify the best parametric
non-mixture cure rate model in this study.
Results: Staging III (OR = 0.41, 95% CI: 0.19 - 0.90, P = 0.026), staging IV (OR = 0.15, 95% CI: 0.04 - 0.50, P = 0.002), Perineural invasion
(OR = 0.41, 95% CI: 0.21 - 0.92, P = 0.007), and lymph node ratio (OR = 0.94, 95% CI: 0.51 - 0.82, P = 0.002) had significant effects on cure
fraction and survival of patients with CRC.
Conclusions: Perineural invasion, Lymph node ratio, and American Joint Committee on Cancer (AJCC) staging should be assessed
as an important factor in modeling survival analysis of patients with CRC. Patients who were in advanced stages of CRC should have
received treatment and appropriate therapies given their shorter survival rates.
