Endocrine Abstracts

MEN2a is a rare genetic endocrine disorder associated with mutation of RET oncogene on chromosome 10. It involves lesions in thyroid, parathyroid and adrenal glands. Medullary thyroid carcinoma is the pathological hallmark and usually the first presentation of this syndrome.

Clinical case: A 64-year-old lady with previous history of hypertension, IHD, and hypercholesterolemia was referred to Endocrine clinic after she was incidentally found to have high calcium (3.2) and inappropriately high PTH and was diagnosed as having primary hyperparathyroidism. There was no previous history of any endocrine problems and her BP was well controlled with Atenolol and Lisinopril. Neck ultrasound and SISTAMIBI scan demonstrated a single parathyroid adenoma and she was referred for parathyroidectomy. Intraoperatively the surgeon noticed a firm suspicious looking nodule in the thyroid and took a FNA sample from that nodule which was later reported a Thy3 follicular lesion. The case was discussed in thyroid surgery/Endocrine MDT and it was decided to perform a right hemithyroidectomy. Histopathology showed that the large palpable nodule was actually benign but it incidentally showed a 1 mm papillary carcinoma and 1.5 mm medullary carcinoma. The presence of primary hyperparathyroidism and medullary thyroid carcinoma raised the possibility of MEN2a. Genetic testing and calcitonin levels are awaited. Urinary metanephrine levels (checked twice) are normaI.

If RET oncogene is positive, this would make an atypical case of MEN2a because of the late presentation (usually presents in third decade) and atypical presentation (usually the first presentation is with medullary thyroid carcinoma followed by phaeochromocytoma).