Endocrine Abstracts

Higher serum TSH has been recently postulated as a predictor of thyroid malignancy in nodular thyroid disease. In addition, some reports have demonstrated its association with more advanced stages of differentiated thyroid cancer (DTC).

Material and methods: We collected retrospectively preoperative serum TSH from patients who underwent total thyroidectomy in the period 2005–2011 in a single tertiary center. We recorded demographic data, nodule number, tumour size and final anatomic pathology. Patients with Graves disease or primary hypothyroidism under treatment previous to surgery were excluded, and so were cases with medullar or anaplastic thyroid cancer.

Results: 524 patients including 187 with malignancy; 453 females, 154 with malignancy (34%), as 33 of the 71 males (46.5%). Patients with cancer were younger (51.6±14.7 yr) than those with benign nodules (55.7±14.3 yr, P<0.001). It was uninodular disease in 17.2% of benign disease and 34.2% of diagnosed as malignancy (P<0.0001). Preoperative mean TSH levels were higher in patients with malignancy vs. benign pathology (2.53±2.5 vs. 1.50±1,8; P<0,0001). Out of the 187 cases of DCT, 48 were incidental microcarcinomas (INCM), with mean TSH of 2.10±1.82, still different from bening cases (P=0.004). Excluding these, the mean TSH was 2.68±2.69 in the remaining DTC (P<0.001 vs INCM). There was difference in mean TSH between follicular adenomas (FA) (n:65; 2.51±3) and hyperplastic goitres (n:264; 1.21±1.2); but no between FA and CPT (P=0.25). Median TSH in DTC shows a tendency to be higher with bigger tumour size (1.78 vs 2.14; ≤2 vs >2 cm; P=0.099).

Conclusions: Our series, as others published, depicts benign lesions having lower TSH level, with difference between pathologic subtypes, while DTC, and similarly to FA, being associated with higher level. The correlation among histotype, tumour size and TSH level suggests a role of TSH in the carcinogenesis of DTC and pathogenesis of FA.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector