Parathyroid carcinoma: a case report.

Parathyroid carcinoma (PC) is an uncommon cause of primary hyperparathyroidism (pHPT). The tumor is mostly functioning with following high serum calcium and parathyroid hormone (PTH) levels. Consideration of PC in differential diagnosis of pHPT is important because the mortality and the prognosis depend on early recognition and surgical approach. A case of PC in 51-year old female patient with persistent pHPT is reported. A patient, referred with anterior cervical hematoma, dysphagia, underwent neck ultrasound, barium X-ray swallow test and neck computed tomography. On the posterior surface of left thyroid lobe, close to the esophagus the heterogenic lesion with irregular margins was found. The preoperative calcemia was slightly elevated. The patient underwent cervical exploration with parathyroidectomy. Histological exam showed parathyroid lesion with immunohistochemical confirmation of PC. After 2 months follow-up there are no signs of a residual-recurrent disease. Although laboratory tests revealed pHPT preoperatively, no clinical effects of elevated calcium and PTH concentration levels were presented. As histological features are not specific for the differential diagnosis between the parathyroid adenoma and PC, the immunohistochemistry remains the only useful tool for the definite diagnosis.