Assessment of Risk Factors on the Relapse and Death in Patients With Thyroid Cancer in Khorasan Razavi Province, During 2005-2015

Background Thyroid cancer is one of the most common tumors of the endocrine system. Despite its low death rate, its prevalence is high. Different factors affect the incidence, recurrence, and mortality in patients with thyroid cancer.  Objective This study aimed to determine the effective factors in the relapse and mortality rates of thyroid cancer. Methods In this retrospective with a cross-sectional design, 631 cases of thyroid cancer with papillary and follicular pathology were assessed. They were referred to Imam Reza, Ghaem, and Sina hospitals. The effects of various demographic and clinical factors on the survival and relapse of patients were evaluated using parametric and semi-parametric model analysis. The obtained data were analyzed in R and SPSS. Findings Most of the patients were female (74.8%). Their mean±SD age of the diagnosis was 39.74±15.7 years. Seventeen (2.7%) patients died, and 140(22.2%) patients had a recurrence. In multivariate analysis with the recurrence event, age of diagnosis, and tumor size were significant factors in the semi-parametric model, and the age of diagnosis, tumor size, and distant metastases were significant factors in the parametric model. In multivariate analysis with the death event, age of diagnosis, and weight were significant factors in the semi-parametric model, but the age of diagnosis and gender were significant factors in the parametric model (P<0.05). Conclusions Clinical factors such as gender, age of diagnosis, tumor size, weight, and distant metastasis are effective factors in cancer recurrence and death. Therefore, it is necessary to pay attention to these factors in the treatment of patients.