Parathyroid carcinoma

Parathyroid carcinoma is a rare cancer that forms in the tissues of one or more of the four parathyroid glands in the neck, the glands that make parathyroid hormone and so help keep serum calcium normal. It is far less common than parathyroid adenoma, with fewer than a thousand documented cases since its first description in 1904, and it is thought to arise through progression from adenoma to carcinoma. Most patients have moderate to severe hypercalcemia and high hormone levels, often with a large neck mass and kidney or bone abnormalities. Risk appears to rise with multiple endocrine neoplasia type 1, familial isolated hyperparathyroidism and hyperparathyroidism-jaw tumor syndrome. Diagnosis needs pathological examination of tissue, and treatment is aggressive surgical excision, with calcimimetic drugs such as cinacalcet used to lower calcium.