Endocrine Abstracts

Hyperfunctional nodules of the thyroid are rarely associated with thyroid cancer, for these reason are rarely biopsied. Although multiple theories have being proposed, the relationship is still uncertain. After performing a MEDLINE literature search, we found in multiple retrospectives analysis, that patients with hyperthyroidism with hyperfunctional nodules have an estimated of 0.3–16.3% prevalence of malignancy. In our study forty-eight hyperthyroid cases were prospectively investigated to provide information about the association between hyperthyroidism and thyroid cancer. Historical, biochemical and radiological characteristics of the case subjects and their nodules were also analyzed. All nodules greater than 1 cm in diameter, nodules 5–10 mm size diameter if they had calcification were fine-needle biopsied (FNAB) under ultrasound guidance. The biopsy samples were cytologically asses (by the BETHESDA classification) and we found 77% of benign nodules, 2% of nodules presented with atypia of undetermined significance or follicular lesion of undetermined significance, 8.3% were malignant nodules, and 10.4% were nondiagnostic or unsatifactory. All patients with a biopsy diagnosis of malignant underwent surgery. Thyroid malignancy (micro- or macrocarcinoma) diagnosed pre-operatively in all four cases by US-guided FNAB was confirmed by the pathology obtained after the surgery. Papillary thyroid carcinoma was identified in two patients (4.17%), and Follicular thyroid carcinoma was found in two patients (4.17%). These data demonstrate a higher than expected incidental cancer rate in hyperthyroid patients compared with euthyroid subjects with nodular goiter. Our purpose is to stress the point that, although hyperfunctioning thyroid nodules are rarely described as malignant in the literature, FNAB should not be restricted to cold nodules, in view of our data and others published reports.