Endocrine Abstracts

Background: Papillary Thyroid Carcinoma after Radioactive Iodine therapy for Graves’ disease is rare with few cases reported in literature. Presentation of case A 28 years gentleman, presented with multiple non tender swellings in the anterior aspect of the neck, insidious in onset, initially started as a single swelling in the left side of the size 3×2 cm. Three years prior, he received I 131 therapy for Graves thyrotoxicosis. Thereafter, developed hypothyroidism after 6 to 7 months and was started on thyroxine supplementations at 50 µg/day. His mother was diagnosed with Papillary thyroid carcinoma age of 54 years. On head and neck examination, he had multiple swellings over bilateral neck with enlarged cervical lymph-nodes levels II, III, V. Investigations Ultrasound neck reported a right lobe vascular mid pole lesion of 7×7 mm with rim calcification, the isthmus contained a 8×6×5 mm well-defined lesion with micro calcification and increased vascularity, the left lobe mid pole had an ill-defined heterogeneous 28 x 21×16 mm lesion with micro calcification, the left neck had multiple in large lymph nodes. A guided FNAC was done from the thyroid nodules and cervical lymph nodes which was suspicious of Papillary thyroid carcinoma with cervical lymph node metastasis. Preoperative laryngoscopy bilateral vocal cords the mobile. Treatment He underwent Total thyroidectomy with bilateral central compartment lymph-node dissection, left selective lymph-node dissection(Level II &III) and right selective lymph-node dissection (Level II, III, IV&V). At operation, the left lobe was enlarged with a hard nodule measuring 2×2 cm, in the right lobe of the thyroid a small node measuring 0.5 cm was seen with extensive bilateral lymph node involvement in the central and lateral compartments. Visual identification and recurrent laryngeal nerve (RLN) neuromonitoring was done, left RLN and right RLN had electromyography signals of 1742μV and 572μV respectively. All four parathyroids were visually identified and preserved. Gross examination of the specimen revealed multifocal greyish white tumour tissue in both lobes of the thyroid. Histopathology reported multifocal papillary thyroid carcinoma of classical type. Seventeen out of the 26 resected lymph nodes in the central compartment and bilateral lateralcompartment showed metastatic foci. Based on the above findings a diagnosis of Classical multifocal papillary thyroid carcinoma pT1pN1bpMx was made. Postoperative period was uneventful and he made a good recovery.

Discussion: Literature rare in post radioactive ablation