Thyroid-Stimulating Hormone, Thyroid Hormones and Risk of Papillary Thyroid Cancer: A Nested Case-Control Study
Menée aux Etats-Unis à partir d'échantillons sériques prélevés avant le diagnostic sur 741 patients atteints d'un cancer papillaire de la thyroïde et sur 741 témoins, cette étude évalue l'association entre le niveau d'hormones thyroïdiennes et le risque de développer la maladie
Background:The effects of thyroid-stimulating hormone (TSH) and thyroid hormones on the development of human papillary thyroid cancer (PTC) remain poorly understood. Methods:The study population consisted of 741 (341 women, 300 men) histologically confirmed PTC cases and 741 matched controls with pre-diagnostic serum samples stored in the Department of Defense Serum Repository. Concentrations of TSH, total T3 (TT3), total T4 (TT4), and free T4 (FT4) were measured in serum samples. Conditional logistic regression models were used to calculate ORs and 95% CIs. Results:The median time between blood draw and PTC diagnosis was 1,454 days. Compared to the middle tertile of TSH levels within the normal range, serum TSH levels below the normal range were associated with an elevated risk of PTC among women (OR=3.74, 95% CI: 1.53, 9.19) but not men. TSH levels above the normal range were associated with an increased risk of PTC among men (OR=1.96, 95% CI: 1.04, 3.66) but not women. The risk of PTC decreased with increasing TSH levels within the normal range among both men and women (Ptrend=0.0005 and 0.041, respectively). Conclusions:We found a significantly increased risk of PTC associated with TSH levels below the normal range among women and with TSH levels above the normal range among men. An inverse association between PTC and TSH levels within the normal range was observed among both men and women. Impact:These results could have significant clinical implications for physicians who are managing patients with abnormal thyroid functions and those with thyroidectomy. http://cebp.aacrjournals.org/content/cebp/early/2017/04/04/1055-9965.EPI-16-0845.full.pdf