Parathyroid carcinoma--problems in diagnosis and treatment.

Four patients with parathyroid carcinoma operated on at the Karolinska Hospital were reviewed. In three patients the parathyroid carcinoma was suspected at the primary operation and successfully treated with excision of the tumour and ipsilateral hemithyroidectomy. In one patient the diagnosis was made only after local recurrence of the tumour and the appearance of lung metastasis. Although removal of local recurrence and distant metastasis was not curative, the patient improved for a long period of time. When surgical resection did not successfully control the hypercalcemia, Mithramycin, 12.5 micrograms/kg intravenous daily was given for five days. With two days interruption the treatment was repeated. The hypercalcemia could in this manner be controlled for almost one and a half years. It is concluded that parathyroid carcinoma is a relatively rare endocrine tumour which may be cured by adequate initial operation. When surgery is not feasible to control hypercalcemia, Mithramycin seems to be the drug of choice even for long-term therapy.