Endocrine Abstracts

Thyroid nodules are common and majority is benign. Even so, clinicians and patient always concern about the risk for malignancy. In the past it was believed that hyperthyroidism excluded the possibility of a thyroid carcinoma. We describe here two patients presenting “hot” thyroid nodules with final diagnosis of papillary thyroid carcinoma. Informed consent was obtained. Case 1: A 39-years-old female, presenting with irritability, disquiet, and neck swelling. A nodule was palpable in left lobe. Cervical ultrasonographic studies showed a nonhomogeneous nodule in an enlarged left lobe. Serum examinations demonstrated hyperthyroidism. 99m Tc and 131I scintigraphy showed hot area corresponding to the nodule in the left lower lobe. A total thyroidectomy was performed and post operative histological examination revealed a papillary carcinoma within the nodule of the lower left lobe. Macroscopically the white nodule measured 1.4 cm and surrounding thyroid tissue had no evidence of infiltration. No metastatic foci were recognized in adjacent tissues. Case 2: A 46-years-old female developed symptoms of neck swelling and palpitations. A large painless hard nodule was palpable in the right lobe of thyroid. Ultrasonography revealed a large right lobe with solid nodule without lymphadenopaties. Thyroid function tests showed TSH undetectable of <0.01 μIU/mL, free thyroxine was 1.99 ng/dL (normal 0.7–1.8), and her triiodothyronine was 5.6 pg/mL (normal 2–4.4). A 99mTc scan demonstrated a “hot” area corresponding to the nodule with a suppressed uptake in the remaining thyroid tissue. RAIU value was 46% (normal =15–35%). Right loboisthmectomy was performed and the histological examination revealed a papillary carcinoma with no signs of angioinvasivity. The surrounding thyroid tissue showed no signs of infiltration or spreading. A completion thyroidectomy revealed metastasis in 5/6 limph nodes. Thyroid carcinoma rarely occurs concomitantly with dominant hyperfunctional nodules. Papillary thyroid cancer within a “hot” nodule is reported to be much less than 1%. These cases illustrated that malignancy cannot be always excluded even in autonomously functioning thyroid nodules consequently all thyroid nodules require careful diagnosis and appropriate management.

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