Localization of parathyroid tumors using endoscopic ultrasonography in primary hyperparathyroidism

Parathyroid adenomas responsible for primary hyperparathyroidism may be dif ficult to detect preoperatively. Furthermore parathyroid adenomas may arise behind the (nodular) thyroid gland, in a deep cervical location, and plans should be plane. The purpose of the present prospective study was to evalu ate echoendoscopy, and to compare its accuracy to that of non invasive test s. Fourteen consecutive patients with primary hyperparathyroidism were pros pectively studied. All patients underwent echoendoscopy, ultrasonography (U S), CT scanning or magnetic resonance imaging (MRI) and Tc 99m sestamibi sc anning before undergoing initial neck exploration. The parathyroid patholog y was a solitary adenoma in 13 patients and a 4 glands hyperplasia in one. All tests were corroborating in 5 cases. Four adenomas were localized to th e correc tside (33%), and no test accurately localized all hyperplastic gla nds. EUS, sestamibi and CT scanning or MRI correctly identified 10 parathyr oid tumors in 14 cases (71%). US correctly localized only 5 adenomas (sensi tivity 36%). The sensitivity of EUS to detect parathyroid adenomas is super ior to US (p<0.05) and comparable to that of other non invasive tests. We c onclude that EUS may be an useful tool to localize parathyroid lesions. Thi s method may replace US prior to initial neck exploration with further mini aturization of probes, or find an intermediate place among invasive and non invasive preoperative localization procedures in patients with persistent o r recurrent PHPT.