Document Type : Original Article

Authors

1 Preventive Medicine and Public Health Research Center, Psychosocial Health Research Institute, Community and Family Medicine Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

2 Breast Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran

3 Preventive Medicine and Public Health Research Center, Psychosocial Health Research Institute, Iran University of Medical Sciences, Tehran, Iran

4 Department of Sociology and Anthropology, Nipissing University, North Bay, Ontario, Canada

Abstract

Background: The multi-state models help more closely study of the factors affecting the survival of patients with breast cancer.
Method: We conducted the present retrospective cohort study on 2030 Iranian patients with breast cancer in 2020. The patients’ follow-up period ranged from 1 month to 15 years. Accordingly, the initial treatment, metastasis, and death were considered as the first, second, and absorbing states, respectively. The multi-state model was utilized for modeling and analyzing the data at a 95% significance level using the MSM package in R software.
Results: The mean age (±SD) of the patients included at diagnosis time was 55.3 (±12.07) years old. The first one year and 5 years adjusted transition probabilities for transitions from the treatment to metastasis estimated as 0.85 (0.15 – 0.89) and 0.45 (0.21 – 0.61), and for metastasis to death transitions, they were estimated as 0.15 (0.1 – 0.21) and 0.55 (0.41 - 0.69), respectively. Moreover, the average sojourn times were estimated as 0.27 and 74.85 months for the treatment and metastasis states, respectively.
Conclusion: The obtained results revealed that over time, the transition probabilities of patients from surgery to metastasis state decreased whereas the transition probabilities from metastasis to death state increased using the multi-state model.

Keywords

This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination, and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi:10.30476/mejc.2021.89311.1519