Abstract
Purpose: There is a sex disparity in papillary thyroid cancer (PTC). Male sex is associated with a higher likelihood of advanced stage disease. This study aimed to examine the significance of sex for extranodal extension (ENE) in PTC. Patients and Methods: We reviewed the data of PTC patients who had undergone initial surgical resection from July 2012 to December 2014 (N = 1531). The effects of sex and other clinicopathological factors on ENE were investigated.Results: Of 1531 patients identified, 377 (24.6%) were male, 816 (53.3%) had positive nodes, and 256 (16.7%) had ENE. Compared with female patients, male patients had a higher risk of ENE (P < 0.001). Multivariable analysis of clinicopathological factors revealed that male sex (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.37 - 2.87; P < 0.001), age older than 60 years (OR, 1.93; 95% CI, 1.08 - 3.35; P = 0.023), extrathyroidal extension (OR, 3.52; 95% CI, 2.42 - 5.14; P < 0.001), bilateral multifocality (OR, 2.18; 95% CI, 1.53 - 3.13; P < 0.001), and more positive nodes were significantly associated with increased risk of ENE. Patients with 6-10 positive nodes were 16.45-fold higher to have ENE than patients with 5 positive nodes or less (95% CI, 11.07 - 24.68; P < 0.001).Conclusion: Male PTC patients had a higher risk of ENE than female. Sex was an independent predictor of ENE. The underlying mechanism needs to be investigated further.
Ultrasonographic Characteristics of the Follicular Variant Papillary Thyroid Cancer According to the Tumor Size
