hTERT expression in thyroid nodule

Purpose: Telomerase is expressed by most malignancies including thyroid cancer. In this study, to evaluate the telomerase activity, we determine the expression of human telomerase reverse transcriptase (hTERT) in benign and malignant thyroid tumors. Methods: We examined the clinical data such as age, sex, and recurrence status of 100 patients that underwent thyroidectomy. Also, we reviewed the pathological data of the tissues (tumor size, lymph nodes, capsular invasion, perivascular invasion, perilymphatic invasion etc.). We checked hTERT expression by Allred scoring system using immunohistochemical staining. Results: 21 patients had benign thyroid nodules and 79 patients had malignant nodules. The average size of benign tumors and malignant tumors were 3.1±1.1 cm and 2.1±1.7 cm, respectively. The hTERT expression was higher in malignant tumors (82.3%) than in benign tumors (9.5%) and that difference was statistically significant. In metastatic lymph nodes status of thyroid cancers, 45 of 65 patients (69.2%) had lymphatic metastases in hTERT positive group, which is much higher than hTERT negative group (P=0.001). Conclusion: In our study, hTERT expression may be used as a prognostic biologic marker in thyroid cancer and also in the diagnosis of malignancy.