Parathyroid carcinoma

This article highlights recent advances in our understanding of the incidence, epidemiology, clinical presentation, evaluation, diagnosis, treatment, and prognosis of parathyroid carcinoma.

The prevalence of parathyroid carcinoma is approximately 0.005% of all cancers. Therefore, parathyroid carcinoma is one of the rarest malignancies known. Patients with parathyroid carcinoma present with clinical symptoms of hypercalcaemia as these cancers are usually hormonally functional. It is not uncommon that patients present with complications of profound hypercalcaemia because of an elevated parathyroid hormone. Parathyroid carcinoma is difficult to diagnose preoperatively unless patients present with metastatic disease. Serum calcium often exceeds 14 mg/dl and serum parathyroid hormone is significantly elevated commonly between three and 10 times of the upper limit. Fine needle aspiration is not recommended because of the risk of parathyromatosis. Treatment includes surgery as a primary form of therapy and this usually follows with postoperative radiotherapy, although its use remains controversial.

Patients with parathyroid carcinoma should undergo adequate surgical excision with an attempt of preserving vital structures such as the recurrent laryngeal nerve. Often en bloc resection of the ipsilateral thyroid lobe with comprehensive level VI dissection is required. Postoperative radiotherapy should be considered in most cases.