Ectopic Parathyroid Adenoma Extending to the Aortic Arch: A Case Report

Presentation Number: MON 315
Date of Presentation: April 3rd, 2017

Najala Orrell1, Nisha Nigil Haroon*2 and Boji Varghese3
1Royal College of Surgeons in Ireland, Dublin, Ireland, 2Northern ontario school of medicine, Toronto, ON, Canada, 3Health Sciences North, Sudbury, Canada

Abstract

We report the case of an 82 year old Caucasian woman who presented with severe hypercalcemia and primary hyperparathyroidism. After advanced imaging, the presence of a metabolic active paraesophageal mass was detected. Surgical removal and histopathology demonstrated an ectopic parathyroid adenoma.

The patient had severe hypercalcemia, hypophosphatemia (serum phosphorus 0.65 mmol/L) and mild renal failure (serum creatinine 163mmol/L). Serum iPTH levels ranged between 22 and 62.1 mmol/L. Serum ALP level was normal at 106 U/L. Thyroid function was normal. She was started on Cinacalcet to lower serum calcium.

CT scan of the neck revealed the presence of a heterogeneously enhancing mass arising from the left lobe of the thyroid gland and extending to the distal cervical and proximal thoracic esophagus. The lesion was seen extending to the thoracic aortic arch. It measured 3.2 cm*1.8c m*1.9 cm. Technetium labeled MIBI scan with SPECT/CT showed increased activity in the paraesophageal area. BMD showed osteoporosis.

During excisional biopsy, the mass was seen extending inferiorly from the parathyroid area to the paratracheal, paraesophageal and superior mediastinum. Histopathology of the surgical specimen confirmed the presence of an ectopic parathyroid adenoma.

The post operative course was complicated by hungry bone syndrome, characterized by hypocalcaemia, hypophosphataemia, hypomagnesaemia and suppressed PTH.

Approximately 15 % of parathyroid adenomas are ectopic in origin. Ectopic parathyroid adenomas arising below the level of clavicle are referred to as a mediastinal parathyroid adenomas. Common clinical presentation presents with persistent hypercalcemia and parathyroid bone disease. There is often a delay in diagnosis. However, SPECT/CT and surgical exploration have resulted in a higher prevalence and earlier treatment for these lesions. Our case highlights a rare presentation of ectopic parathyroid adenoma extending to the mediastinum and aortic arch.

 

Nothing to Disclose: NO, NN, BV