Replantation of cryopreserved human parathyroid tissue

Twenty-five patients with permanent postoperative hypoparathyroidism received cryopreserved parathyroid autografts. Twelve patients had undergone cervical re-operations due to persistent or recurrent hyperparathyroidism and 10 patients had malfunction of a fresh autograft after total parathyroidectomy. Hypoparathyroidism occurred in 2 patients after subtotal parathyroidectomy and in 1 after the resection of a solitary adenoma following previous thyroid resection. The viability of the tissue was examined histologically prior to replantation in 22 patients and the amount of tissue needed for transplantation was determined by the ratio of necrotic cells vs. viable cells in the material. The patients were examined between 6 months and 125 months (median: 40 months) after replantation. Pre-operatively each patient required high doses of calcium and vitamin D metabolites to establish normocalcemia. This medication was reduced postoperatively, with 16 patients requiring no supplemental treatment. Nine patients still needed low doses of calcium and/or vitamin D. At follow-up all patients were free of hypocalcemic symptoms. Our results demonstrate that replantation of autologous cryopreserved parathyroid tissue is safe and effective therapy for permanent postoperative hypoparathyroidism. Thus, we regard it as an essential part of today's parathyroid surgery.