[Sonographic diagnosis of parathyroid carcinoma]

Prognosis and survival of patients suffering from parathyroid carcinoma are completely dependent on correct surgical therapy in form of an en-bloc resection of the tumour. A correct preoperative diagnosis of this rare carcinoma is therefore absolutely mandatory in order to perform a curative operation. We demonstrate a case of parathyroid carcinoma in which scintigraphy and CT diagnostics did not produce the right diagnosis. Preoperative high-resolution ultrasound (8 MHz) in combination with power-Doppler-sonography, however, led to the right diagnosis by demonstrating the correct topography, signs of malignancy and the feeding vessels of the tumour. As it could be demonstrated that the inferior thyroid artery was displaced by the tumour and was not a tumour feeding artery, the inferior thyroid artery was an important additional landmark for making the decision between thyroid or parathyroid carcinoma. The use of power-Doppler-sonography for identification of feeding arteries associated with parathyroid carcinoma in addition to high-resolution small parts sonography is of great value for the distinction between thyroid or parathyroid tumour.