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Paper 9 (1100)
LONG-TERM FUNCTIONALITY OF CRYOPRESERVED PARATHYROID AUTOGRAFTS: A 13- YEAR PROSPECTIVE ANALYSIS.
Background: The functionality of cryopreserved heterotopic parathyroid autotransplantation (CHPA) is not well defined. We evaluated the Results: of delayed CHPA for the treatment of surgically-induced hypoparathyroidism.
The 26th Annual Meeting of the American
Association of Endocrine Surgeons
April 3rd- 5th,2005 - Paradisus Riviera Cancun.
Cohen MS, Wells SA Jr , Moley JF, Doherty GM, Sicard GA, Skinner MK , Norton JA, DeBenedetti MK, Lairmore TC
Washington Univ. School of Medicine, Duke Univ. Medical School, Stanford University Medical School,Univ. of Michigan School of Medicine
Methods: Since November 1991, 448 parathyroid samples from 436 patients were cryopreserved at our institution. Of these, 29 patients underwent 34 CHPA procedures, with placement of 20 to 25 pieces of parathyroid tissue (approx. 50-75 mg) into the forearm. Outcomes were determined based on peripheral parathyroid hormone (PTH) levels, and where available, PTH gradients between grafted and non-grafted arms. Results: were defined as completely functional (patients with normal PTH and calcium levels off all calcium/vitamin D supplementation), partially functional (normal PTH levels and mild hypocalcemia on calcium supplementation), nonfunctional (low PTH levels and dependent on calcium/vitamin D supplementation).
Results: Prospective data were available for 26 patients undergoing 30 CHPA procedures (9 patients with MEN1, 4 with MEN2A, 1 with MEN2B, and 12 with non-hereditary hyperparathyroidism). The mean follow-up interval was 2 years. Eleven of thirty autografts (37%) were completely functional, 5 autografts (17%) were partially functional, and the remaining 14 autografts (46%) were nonfunctional. No patient with CHPA had graft-dependent hyperparathyroidism. Of the 14 patients (15 autografts) with MEN, 6 autografts (40%) were fully functional and 3 were partially functional (20%). The median cryopreservation period was 5.6 months (range 1 week to 22 months) for functional autografts and 5.5 months (range 2 weeks to 106 months) for nonfunctional autografts (p =0.26).
Conclusions: Based on these data and previous studies, approximately half of delayed, cryopreserved parathyroid autografts are functional. In this study 37% achieved full competency off supplements. Some patients have evidence of graft function with normal PTH levels, but are not normocalcemic. Results: were similar for patients with MEN and non-hereditary hyperparathyroidism. Duration of cryopreservation was not a significant indicator of graft failure however no functional autograft was observed beyond 22 months of preservation. CHPA is a useful modality for patients who fail immediate autotransplantation to avoid permanent hypocalcemia.