Leukocyte Telomere Length and Risk of Papillary Thyroid Carcinoma.

Abstract

Telomere length may contribute to predisposition to papillary thyroid cancer (PTC). To test this hypothesis, we examined the association between leukocyte telomere length and PTC risk. Case-control study in a Chinese Han population. A total of 1200 PTC cases and 1201 age- and sex-matched healthy controls were included in the study. ORs and 95% CIs were calculated by logistic regression. Short relative telomere length (RTL) was significantly associated with elevated risk of PTC (OR = 1.61, 95% CI = 1.35 to 1.92; P = 1.30 × 10-7). Interestingly, when individuals were categorized into four groups on the basis of quartile distribution of relative telomere length (RTL) in controls, we observed a reverse U-shaped association between telomere length and PTC risk. Compared with those in the first (the longest) quartile as the reference group, ORs (95% CIs) were 5.61 (4.04 to 7.78) (P = 6.10 × 10-25), 9.33 (6.78 to 12.83) (P = 6.99 × 10-43), and 1.23 (0.83 to 1.81) (P = 0.300) for individuals in the second, third, and fourth (the shortest) quartiles, respectively. This reverse U-shaped relationship was more apparent in younger individuals. Our findings suggest that RTL is significantly associated with susceptibility to PTC. There is an obvious reverse U-shaped association between telomere length and PTC risk. Telomere length may be a potential pronouncing biomarker to identify individuals with a high risk of developing PTC.