Parathyroid autotransplantation with total thyroidectomy for thyroid carcinoma: long-term follow-up of grafted parathyroid function.

BACKGROUND: Permanent hypoparathyroidism is a major complication of thyroidectomy. Autotransplantation of parathyroid glands has been attempted to prevent this complication. However, no direct data have been available to assess grafted parathyroid function after long-term follow-up in terms of the serum intact parathyroid hormone (PTH) concentration. METHODS: Eighty-four consecutive patients with differentiated thyroid carcinoma who underwent total thyroidectomy and bilateral modified neck dissection from 1992 to 1996 were enrolled. They concomitantly underwent total parathyroidectomy and autotransplantation of all parathyroid glands to the pectoralis major muscle. The serum intact PTH concentration was periodically measured as an index of grafted parathyroid function. RESULTS: The mean follow-up was 34 months. In all autotransplanted patients serum intact PTH concentrations fell below detectable limits immediately after surgery. They were restored to the normal range within 1 month postoperatively and were maintained during observation in 80 (95%) of 84 patients. Seventy-eight of 80 patients with normal intact PTH values were normocalcemic without any treatment and the remainder were normocalcemic with 1 microgram of 1 alpha-vitamin D3. Four hypoparathyroid patients were normocalcemic with 2 micrograms of 1 alpha-vitamin D3. The postoperative average serum intact PTH concentration of patients having more than 2 autotransplanted parathyroid glands was almost equal to that of patients with preservation of the parathyroid glands in situ. The incidence of permanent hypoparathyroidism was inversely correlated with the number of autotransplanted parathyroid glands. CONCLUSIONS: The recovery patterns of the intact PTH concentration indicate that the glands were grafted successfully and functioned for a long period. This feasible method of parathyroid autotransplantation bears comparison with the previous reports in terms of the incidence of permanent postoperative hypoparathyroidism, and it can be performed simply and is reproducible.