Solitary phalangeal brown tumour in primary hyperparathyroidism: Report of a rare presentation.

Parathyroid adenoma is the most common cause of primary hyperparathyroidism. Severe cases of primary hyperparathyroidism manifest as osteitis fibrosa cystica generalisata, characterized by generalized bone loss with increased bone resorption, including both subperiosteal and endosteal surfaces. The most common sites for formation of fibrotic cystic lesions (brown tumors) are in the long bones and jaw which present as swelling, pathological fracture, and/or bone pain, usually involving multiple sites. Here, we describe an unusual presentation of a solitary brown tumor in a young male who initially presented to the hand surgeon with a history of right thumb swelling following trivial trauma. Further detailed clinical, biochemical, scintigraphic (Tc 99m methylene diphosphonate scintigraphy and Tc 99m Sestamibi scintigraphy), and radiological investigations aided definitive diagnosis and treatment. The causative parathyroid adenoma was excised curing hyperparathyroidism and the lesion regressed substantially.