title: Parathyroid cryopreservation after parathyroidectomy: a worthwhile practice?
abstract: BACKGROUND
  Parathyroid cryopreservation is often utilized for patients having parathyroidectomy. This allows for future autotransplantation if a patient becomes permanently hypocalcemic after surgery. However, the practice of cryopreservation is costly and time-consuming, while the success rate of delayed autotransplantation is highly variable. We sought to determine the rate and outcomes of parathyroid cryopreservation and delayed autotransplantation at our institution to further evaluate its utility.
  
  
  METHODS
  At our institution, 2,083 parathyroidectomies for hyperparathyroidism (HPT) were performed from 2001 to 2010. Of these, parathyroid cryopreservation was utilized in 442 patients (21 %). Patient demographics, preoperative diagnoses, and other characteristics were analyzed, as well as the rate and success of delayed autotransplantation.
  
  
  RESULTS
  Of the 442 patients with cryopreservation, the mean age was 55 ± 1 years and 313 (70.8 %) were female. A total of 308 (70 %) had primary HPT, 46 (10 %) had secondary HPT, and 88 (20 %) had tertiary HPT. Delayed autotransplantation of cryopreserved parathyroid tissue was used in 4 (1 %) patients at an average time of 9 ± 4 months after initial surgery. Three of the 4 patients remained hypoparathyroid after this procedure. The single cured patient underwent the procedure only 4 days after the initial parathyroidectomy.
  
  
  CONCLUSIONS
  Although cryopreservation was used in over one-fifth of patients undergoing parathyroidectomy, the need for parathyroid reimplantation was very low (1 %). Furthermore, the success rate of parathyroid autotransplantation was poor in these patients. Therefore, the continued practice of parathyroid cryopreservation is questionable.
authors.affiliation: Section of Endocrine Surgery, Department of Surgery, University of Wisconsin, Madison, WI, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Shepet
authors.forename: Amal
authors.initials: A
authors.lastname: Alhefdhi
authors.forename: Reid
authors.initials: R
authors.lastname: Usedom
authors.forename: Rebecca
authors.initials: R
authors.lastname: Sippel
authors.forename: Herbert
authors.initials: H
authors.lastname: Chen
mesh_terms: D015925:Cryopreservation / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000601:surgery; D006962:Hyperparathyroidism, Secondary / Q000601:surgery; D006996:Hypocalcemia / Q000209:etiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000637:transplantation*; D016105:Parathyroidectomy / Q000009:adverse effects; D012189:Retrospective Studies; D014182:Transplantation, Autologous / Q000706:statistics & numerical data