Nonfunctioning parathyroid carcinoma: case report and review of literature.

OBJECTIVE

To report a case of nonfunctioning parathyroid carcinoma that was incidentally found during a thyroidectomy for multinodular goiter.

METHODS

We present a case report, detailing the clinical course and histologic findings in a patient with a nonfunctional parathyroid carcinoma. The related literature is also reviewed.

RESULTS

A 67-year-old woman presented with a 30-year history of a multinodular goiter that was symptomatic. A total thyroidectomy was performed. Histologic examination revealed not only a multinodular thyroid but also a mass in the left lobe, which was diagnostic of a parathyroid carcinoma. Serum calcium and parathyroid hormone levels were normal postoperatively. Eleven months after the initial operation, a suprasternal mass developed, and she underwent neck reexploration and subtotal resection of an invasive recurrent nonfunctioning parathyroid carcinoma. The serum parathyroid hormone and calcium levels were normal before and after the operation. Postoperatively, the patient underwent radiation therapy. Twenty-three months after the initial operation, a computed tomographic scan of the chest revealed an interval increase in size of a nodule in the left lower lobe of the lung, and 30 months after her initial operation, she underwent resection of an isolated, 1-cm (greatest diameter), metastatic parathyroid carcinoma in the left lower lobe of the lung. The patient is currently doing well without evidence of recurrent disease.

CONCLUSION

Nonfunctioning parathyroid carcinomas are difficult to diagnose and to treat. Recurrent disease after operation is common, and radiation therapy may help stabilize tumor growth. Patients with nonfunctioning parathyroid carcinomas appear to have a poorer prognosis than do those with functioning parathyroid cancers.