Multiglandular Parathyroid Carcinoma: Case Report and Review of the Literature

Abstract

To report the fifth case of multiglandular parathyroid carcinoma and highlight the necessity of bilateral neck exploration in some circumstances. We report a case of simultaneous bilateral and multiglandular parathyroid carcinoma in a 48-year-old woman presenting with primary hyperparathyroidism. Ultrasonography revealed a 24- by 24- by 34-mm nodule on the right lobe of the thyroid and a 20- by 20- by 32-mm parathyroid gland inferior to the left thyroid lobe. Technetium Tc 99m sestamibi scan revealed bilateral increased uptake consistent with the parathyroid glands. She was treated with bilateral neck exploration and parathyroidectomy with en bloc resection of the adjacent thyroid lobe in the right lower gland and parathyroidectomy with resection of surrounding soft tissue in the left lower gland. The presence of a thick fibrous capsule, invasion of surrounding tissues, trabecular and solid growth pattern without necrotic foci, and vascular invasion on pathology slides enabled the diagnosis of parathyroid carcinoma of both glands. Her calcium and parathyroid hormone levels were within normal limits during a follow-up period of 4 years. Since surgical resection offers the only curative treatment and initial operation may be the determinant of survival, a high index of suspicion for carcinoma both clinically and intraoperatively is vital. We aim to reemphasize that bilateral neck exploration in select cases of parathyroid carcinoma should be considered if there is concrete evidence of a second tumor, since parathyroid carcinoma can coexist with hyperplasia, adenoma, or even carcinoma of other parathyroid glands.