The Prevalence of Thyroid Cancer in Iran: a Systematic Review and Meta-analysis.

Cancer is the most common malignant tumor of the endocrine glands and comprises 1% of all malignant cancers and its incidence is still increasing. No comprehensive study summarizing the results of these studies was found. Therefore, this study aimed to determine the prevalence of thyroid cancer in Iran in a systematic review and meta-analysis. In this review, studies were extracted by searching the national and international databases of SID, MagIran, IranMedex, IranDoc, and Google Scholar, Cochrane, Embase, ScienceDirect, Scopus, PubMed, and Web of Science (WoS) from 1997 to September 2019. Simple random effects model was used for data analysis and heterogeneity of studies was investigated with I 2 index. Data were analyzed using Comprehensive Meta-Analysis (version 2) software. In 28 reviewed articles, the prevalence of thyroid cancer in Iran was reported to be 3.5% with a sample size of 100,869 (95% CI: 2.7-4.4%). Regarding heterogeneity on the basis of meta-regression, there was no significant difference between the effect of the year of study ( P  = 0.531) and sample size ( P  = 0.864) and the prevalence of thyroid cancer in Iran. The results of this study indicated that the prevalence of thyroid cancer is high in Iran. Therefore, appropriate strategies should be put in place by providing feedback to hospitals in order to improve the aforementioned situation, and troubleshoot and monitor at all levels.