Endocrine Abstracts

Introduction: In 1974, the first case of concomitant thyroid and parathyroid disease was reported. Non-medullary thyroid carcinoma has been reported in 6% of patients with Primary hyperparathyroidism. However, the simultaneous occurrence of parathyroid carcinoma along with non-medullary thyroid carcinoma is extremely rare.

Case report: We report a case of 60-year-old woman with a history of Diabetes Mellitus type 2 and hypertension. She had no family history of thyroid cancer or multiple endocrine neoplasia type 1 or 2. She presented with symptoms of severe hypercalcemia with calcium level at 13.83 mg/l (8.8–10.4 mg/l) and had increased serum parathyroid hormone level (569 pg/ml). Physical examination revealed an approximately 3 cm left nodular thyroid without recurrent nerve palsy or cervical lymphadenopathy. A bone density test performed showed no evidence osteoporosis. On ultrasound of the neck, her thyroid was multinodular with a 4–10 mm highly hypoechoic nodules associated with a large nodule at the upper pole of the left thyroid which measured 3 cm. Technetium-99 m methoxyisobutylisonitrile (MIBI) cervical and mediastinal substraction scintigraphy scans revealed increased uptake of left polar superior area of thyroid. Blood and urine tests and calcitonin levels were normal, making multiple endocrine neoplasia type 2 very unlikely. The patient received a total thyroidectomy, left parathyroidectomy, and central and lateral cervical lymph node dissection were performed in consideration of extemporaneous histological examination suggestive of a papillary micro-carcinoma of the left lobe and the suspicious aspect of the 4 cm parathyroid formation which was hard and adherent to the thyroid and difficult to dissect from the vascular axis. The definitive anatomopathological examination of the operative specimen showed a bifocal papillary micro carcinoma with vesicular component. The left parathyroid gland was the site of significant multinodular hyperplasia with central nodule involvement with vascular emboli and capsular invasion. Considering the severity of the hypercalcemia and macroscopic appearance as well as the histological aspect, the diagnosis of parathyroid carcinoma was retained. Postoperatively, the patient had normocalcemia in conjunction with PTH levels measured 30 pg/ml. Investigations showed no distant metastasis.

Conclusion: In conclusion incidence of primary hyperparathyroidism due to parathyroid carcinoma along with non-medullary thyroid carcinoma is extremely rare. In patients with severe hypercalcemia, parathyroid carcinoma should be considered a possible underlying cause, and if the operative finding supports the suspicion of parathyroid carcinoma, an en bloc resection of the parathyroid tumor and the adjacent thyroid lobe should be performed.