Intraoperative diagnostic strategy to distinguish parathyroid adenomas from metastatic thyroid cancer.

Objective: To report the limitations of frozen section examination and the value of intraoperative tissue aspiration for parathyroid hormone assay to distinguish parathyroid adenomas from metastatic thyroid carcinoma.

Methods: We describe 2 patients with a biochemical diagnosis of primary hyperparathyroidism who underwent intraoperative frozen section analysis of suspected parathyroid tumors. Parathyroid gland aspiration for parathyroid hormone was also performed for confirmation.

Results: The intraoperative frozen section examination of the suspected parathyroid tumors inaccurately identified the tumors as follicular carcinomas. The parathyroid gland aspirate, however, accurately substantiated the presence of parathyroid adenomas, rather than follicular cancers.

Conclusion: Aspiration of a suspected parathyroid tumor for parathyroid hormone assay accurately determines whether a nodule is a parathyroid gland and facilitates intraoperative decision making, especially when frozen section diagnosis is misleading.