Parathyroid carcinoma


Parathyroid carcinoma is a rare cancer resulting in parathyroid adenoma to carcinoma progression. It forms in tissues of one or more of the parathyroid glands.
It is rare, and much less common than parathyroid adenoma.
It can be difficult to excise.

Signs and symptoms

Most patients experience moderate to severe hypercalcemia and high parathyroid hormone levels. A large mass in the neck is often seen, and kidney and bone abnormalities are common.

Risk factors

Parathyroid cancer occurs in midlife at the same rate in men and women.
Conditions that appear to result in an increased risk of parathyroid cancer include multiple endocrine neoplasia type 1, autosomal dominant familial isolated hyperparathyroidism and hyperparathyroidism-jaw tumor syndrome. Parathyroid cancer has also been associated with external radiation exposure, but, most reports describe an association between radiation and the more common parathyroid adenoma.

Diagnosis

Treatment

Parathyroid carcinoma is sometimes diagnosed during surgery for primary hyperparathyroidism. If the surgeon suspects carcinoma based on severity or invasion of surrounding tissues by a firm parathyroid tumor, aggressive excision is performed, including the thyroid and surrounding tissues as necessary.
Agents such as calcimimetics are used to mimic calcium and are able to activate the parathyroid calcium-sensing receptor, therefore lowering the calcium level, in an attempt to decrease the hypercalcemia.