title: Successful parathyroid tissue autograft after 3 years of cryopreservation: a case report.
abstract: After a total parathyroidectomy, well-established protocols for the cryopreservation of parathyroid tissue and for the delayed autograft of this tissue exist, especially in cases of secondary hiperparathyroidism (HPT) or familial or sporadic parathyroid hyperplasia. Although delayed autografts are effective, the published success rates vary from 10% to 83%. There are numerous factors that influence the viability, and therefore the success, of an autograft, including cryopreservation time. Certain authors believe that the tissue is only viable for 24 months, but there is no consensus on how long the parathyroid tissue can be preserved. A 63-year-old male who was diagnosed with sporadic multiple endocrine neoplasia type 1 and primary hyperparathyroidism, and was submitted to a total parathyroidectomy and an autograft in the forearm. The implant failed, and the patient developed severe hypoparathyroidism in the months following the surgery. Thirty-six months after the total parathyroidectomy, the cryopreserved autograft was successfully transplanted, and hypoparathyroidism was reversed (most recent systemic parathyroid hormone, PTH, of 36 pg/mL, and total calcium of 9.1 mg/dL; no oral calcium supplementation). The case presented here indicates that cryopreserved parathyroid tissue may remain viable after 24 months in storage, and may retain the capacity to reverse permanent postsurgical hypoparathyroidism. These data provide reasonable evidence that the time limit for cryopreservation remains undetermined and that additional research would be valuable.
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Ana K N
authors.initials: AK
authors.lastname: Leite
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Climério P do N
authors.initials: CP
authors.lastname: Junior
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Sérgio S
authors.initials: SS
authors.lastname: Arap
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Ledo
authors.initials: L
authors.lastname: Massoni
authors.affiliation: Endocrinology Division, Endocrine Genetics Unit, HCFMUSP, São Paulo, SP, Brazil.
authors.forename: Delmar M
authors.initials: DM
authors.lastname: Lourenço
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Lenine Garcia
authors.initials: LG
authors.lastname: Brandão
authors.affiliation: Department of Surgery, Head and Neck Surgery Section, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, SP, Brazil.
authors.forename: Fábio L de M
authors.initials: FL
authors.lastname: Montenegro
mesh_terms: D064592:Autografts / Q000254:growth & development*; D015925:Cryopreservation / Q000379:methods*; D005542:Forearm / Q000601:surgery; D006801:Humans; D007011:Hypoparathyroidism / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000637:transplantation*; D016105:Parathyroidectomy; D013997:Time Factors; D014022:Tissue Survival