Parathyroid tumors detected by fine-needle aspiration biopsy under ultrasonic guidance.

Ultrasonically-guided fine-needle aspiration biopsy of 52 suspected parathyroid tumors was performed in 42 patients with primary or secondary hyperparathyroidism. Evidence of a parathyroid tumor was detected cytologically in 31 cases; in 14 the lesion could be attributed to the thyroid gland, while in 7 the aspirated material was inadequate. This technique proved to be extremely helpful in differentiating parathyroid tumors from thyroid nodules and in identifying parathyroid lesions having an atypical location or echo pattern.