Preoperative localization of parathyroid adenoma with sonography and 99mTc-sestamibi scintigraphy in primary hyperparathyroidism

PURPOSE: To evaluate the sensitivity, specificity, and usefulness of dual-phase 99mTc-Sestamibi scintigraphy (SS) and sonography (US) of the neck, alone and in combination, as noninvasive adenoma localizing procedures in patients with primary hyperparathyroidism prior to parathyroidectomy. METHODS: We retrospectively analyzed the charts of 79 patients with parathyroid (PT) adenomas and confirmed diagnosis of hyperparathyroidism who were evaluated with SS and US prior to successful parathyroidectomy. RESULTS: Ninety-three adenomas were removed during bilateral neck exploration. SS alone showed a sensitivity of 76% and a specificity of 79% compared with 89% and 75%, respectively, for US performed after SS on the same day. Combination of the 2 procedures yielded a sensitivity of 89% and a specificity of 90%, with 22% discordant results. The differences in sensitivity and specificity between the 2 techniques alone or in combination were not statistically significant. CONCLUSIONS: No benefit was gained from using both SS and US for the preoperative localization of PT adenomas in patients with primary hyperparathyroidism. Each technique can be negatively affected by thyroid enlargement and nodularity. US, when performed by a skilled operator, is a reliable tool for PT adenoma localization. If the US findings are inconclusive, SS should be used.