Document Type : Research Articles
Department of Public Health, School of Health, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran.
Health Sciences Research Center, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran.
Gastroenterology and Liver Diseases Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Department of Biostatistics, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Department of Biostatistics, Faculty of Health, Mashhad University of Medical Sciences, Mashhad, Iran.
Background and Objectives: Colorectal Cancer (CRC) is the fourth cancer-related cause of death worldwide.
CRC is a multi-stage cancer, which is curable during the early stages of the disease. Therefore, determining the time of
cut-point existence could improve treatment planning and help directly allocate resources. This study aims to determine
the cut point in the age of CRC diagnosis. Methods: This study, covering the course 1985 to 2012, consisted of 345
colorectal cancer patients registered in Taleghani Hospital, Tehran, Iran and followed up to 2013. The cut-point in the
age of CRC diagnosis was obtained using a mixture cure model. The data were analyzed using SPSS and R, V. 20 and
2.15.0, respectively. Results: The results showed that the cut point in the age of CRC diagnosis was 50 years. Based
on our estimation, 65% of the patients diagnosed with CRC at or younger than 50 were cured, while 31% of them
diagnosed older than 50 were cured, and the younger group had a better survival over the older group. Conclusion:
Since access to a cut-point and analysis of created prognostic groups are important in screening and treatment planning,
our results suggested that it is better to estimate the cut-point in the age of curable cancers in early stages via survival
cure models, and the cure rate would increase by CRC timely screening.