Diabetes and thyroid cancer risk: literature review.
Diabetic patients have a higher risk of various types of cancer. However, whether diabetes may increase the risk of thyroid cancer has not been extensively studied. This paper reviews and summarizes the current literature studying the relationship between diabetes mellitus and thyroid cancer, and the possible mechanisms linking such an association. Epidemiologic studies showed significant or nonsignificant increases in thyroid cancer risk in diabetic women and nonsignificant increase or no change in thyroid cancer risk in diabetic men. A recent pooled analysis, including 5 prospective studies from the USA, showed that the summary hazard ratio (95% confidence interval) for women was 1.19 (0.84-1.69) and was 0.96 (0.65-1.42) for men. Therefore, the results are controversial and the association between diabetes and thyroid cancer is probably weak. Further studies are necessary to confirm their relationship. Proposed mechanisms for such a possible link between diabetes and thyroid cancer include elevated levels of thyroid-stimulating hormone, insulin, glucose and triglycerides, insulin resistance, obesity, vitamin D deficiency, and antidiabetic medications such as insulin or sulfonylureas.
Department of Internal Medicine, National Taiwan University Hospital, No. 7, Chung Shan South Road, Taipei 10002, Taiwan.
Shyang-Rong
SR
Shih
Wei-Yih
WY
Chiu
Tien-Chun
TC
Chang
Chin-Hsiao
CH
Tseng
D000368:Aged; D015992:Body Mass Index; D048909:Diabetes Complications / Q000175:diagnosis*; D003920:Diabetes Mellitus / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012306:Risk; D012737:Sex Factors; D013964:Thyroid Neoplasms / Q000150:complications* / Q000175:diagnosis* / Q000453:epidemiology
D007004:Hypoglycemic Agents; D007328:Insulin