Coexistent parathyroid adenomas and Hurthle cell tumors: failure of full detection by subtraction method

Tc-99m sestamibi and I-123 sodium iodide studies were performed on two patients, one with a neck mass and another with suspected hyperparathyroidism. Subtraction images, detected what proved to be Hurthle cell tumors in each case, but coexisting parathyroid adenomas, which were found at surgery, were not visualized. The findings indicate that both types of lesions can occur simultaneously, and that studies are needed to determine whether detailed assays of rate of washout could distinguish between the lesions.