A complex case of Multiple Endocrine Neoplasia type 1 with Metastatic Parathyroid Carcinoma

We describe below a patient with Multiple Endocrine Neoplasia type 1 (MEN type 1) who presented with features of Primary Hyperparathyroidism. However, the actual diagnosis of Parathyroid Carcinoma was delayed until metastases to the lung were discovered. She was also found to have Pituitary Macro adenoma with Silent Acromegaly, with no clinical features whatsoever. She underwent transphenoidal hypophysectomy with postoperative radiotherapy. However, the disease process remained biochemically active necessitating commencement of somatostatin analogues. There is also a tumour at the head of the pancreas which at present is non functional with normal gut hormone profile and normal 24 hour urinary 5-hydroxyl indole acetic acid (5-HIAA) excretion assay. Our case highlights the pitfalls in diagnosing the parathyroid carcinoma due to lack of initial proper histological features. The diagnosis of parathyroid carcinoma was based on histologically confirmed metastases to the lungs. We also discuss below the entity called Silent Acromegaly where patients have biochemically and/or histologically confirmed growth Hormone (GH) excess with no clinical features suggesting Acromegaly. We discuss the benefits of somatostatin analogues in indirectly controlling the rest of the tumours in MEN1 and hypothesise the same for metastatic parathyroid carcinoma. Metastatic parathyroid carcinoma with multiple endocrine neoplasia type 1 is extremely rare. Our case highlights the complexities of managing MEN1 with metastatic parathyroid carcinoma and the dilemmas in dealing with the various aspects of the care.