Diabetes mellitus and risk of thyroid cancer: a meta-analysis

Yohwan Yeo; Seung-Hyun Ma; Yunji Hwang; Pamela L Horn-Ross; Ann Hsing; Kyu-Eun Lee; Young Joo Park; Do-Joon Park; Keun-Young Yoo; Sue K Park

doi:10.1371/journal.pone.0098135

Diabetes mellitus and risk of thyroid cancer: a meta-analysis

PLoS One. 2014 Jun 13;9(6):e98135. doi: 10.1371/journal.pone.0098135. eCollection 2014.

Authors

Yohwan Yeo¹, Seung-Hyun Ma², Yunji Hwang³, Pamela L Horn-Ross⁴, Ann Hsing⁴, Kyu-Eun Lee⁵, Young Joo Park⁶, Do-Joon Park⁶, Keun-Young Yoo¹, Sue K Park⁷

Affiliations

¹ Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.
² Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea; Cancer Research Institute, Seoul National University, Seoul, Korea.
³ Cancer Research Institute, Seoul National University, Seoul, Korea; Department of Biomedical Science, Seoul National University Graduate School, Seoul, Korea.
⁴ Cancer Prevention Institute of California, Fremont, California, United States of America.
⁵ Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
⁶ Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
⁷ Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea; Cancer Research Institute, Seoul National University, Seoul, Korea; Department of Biomedical Science, Seoul National University Graduate School, Seoul, Korea.

Abstract

Introduction: Diabetes mellitus (DM) is an important risk factor for endocrine cancers; however, the association with thyroid cancer is not clear. We performed a systematic review and meta-analysis to clarify the association between thyroid cancer and DM.

Methods: We searched MEDLINE, PUBMED and EMBASE databases through July 2012, using search terms related to diabetes mellitus, cancer, and thyroid cancer. We conducted a meta-analysis of the risk of incidence of thyroid cancer from pre-existing diabetes. Of 2,123 titles initially identified, sixteen articles met our inclusion criteria. An additional article was identified from a bibliography. Totally, 14 cohort and 3 case-control studies were selected for the meta-analysis. The risks were estimated using random-effects model and sensitivity test for the studies which reported risk estimates and used different definition of DM.

Results: Compared with individuals without DM, the patients with DM were at 1.34-fold higher risk for thyroid cancer (95% CI 1.11-1.63). However, there was heterogeneity in the results (p<0.0001). Sensitivity tests and studies judged to be high quality did not show heterogeneity and DM was associated with higher risk for thyroid cancer in these sub-analyses (both of RRs = 1.18, 95% CIs 1.08-1.28). DM was associated with a 1.38-fold increased risk of thyroid cancer in women (95% CI 1.13-1.67) after sensitivity test. Risk of thyroid cancer in men did not remain significant (RR 1.11, 95% CI 0.80-1.53).

Conclusions: Compared with their non-diabetic counterparts, women with pre-existing DM have an increased risk of thyroid cancer.

Publication types

Meta-Analysis
Research Support, Non-U.S. Gov't
Systematic Review

MeSH terms

Cohort Studies
Databases, Bibliographic
Diabetes Complications / epidemiology*
Diabetes Complications / etiology
Diabetes Mellitus / epidemiology*
Female
Humans
Incidence
Male
Risk Factors
Sex Factors
Thyroid Neoplasms / epidemiology
Thyroid Neoplasms / etiology*

Grants and funding

This research was supported by BRL (Basic Research Laboratory) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (2012-0000347) and by the Research Grant Number CB-2011-03-01 of the Korean Foundation for Cancer Research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.