Endocrine Abstracts

A 37-year-old woman presented with a short history of left arm pain. X-ray indicated a lytic lesion of the scapula. Calcium was elevated at 3.25 mmol/l (normal 2.2–2.6) with parathyroid hormone (PTH) 936 pg/ml (5–70). Upon questioning she reported nocturia, polydipsia and dyspepsia. Magnetic resonance imaging revealed brown tumours in the scapula, clavicle and hand. A superior parathyroid adenoma was excised with normalisation of calcium. Bone biopsy of the scapular lesion revealed giant cells in keeping with a brown tumour.

A 52-year-old man presented with left hip pain, and mild nocturia and polydipsia. Radiographs demonstrated a pathological fracture of the femoral neck due to a lytic lesion, which upon biopsy revealed a brown tumour. He had primary hyperparathyroidism (calcium 3.44 mmol/l, PTH 835 pg/ml) due to a right inferior parathyroid adenoma.

A 66-year-old man presented with nausea, headache and a lump on his shin. He had primary hyperparathyroidism (calcium 3.9 mmol/l, PTH >1500 pg/ml). X-rays were in keeping with a brown tumour of the left tibia. A left inferior parathyroidectomy was performed and the tibial mass has decreased in size post operatively.

Brown tumours result from excessive osteoclastic resorption of trabecular bone followed by reparative bone deposition causing expansion beyond the usual shape of the bone. They are a feature of advanced hyperparathyroidism and are seldom seen today. Despite significant hypercalcaemia however, all of these three patients had minimal symptoms, thus perhaps permitting development of this unusual complication.