title: Parathyroid lipoadenomas: a rare cause of primary hyperparathyroidism.
abstract: OBJECTIVE
  To review one institution's experience with parathyroid lipoadenomas and to report the associated clinical characteristics.
  
  
  METHODS
  We present a case series of parathyroid lipoadenomas. A parathyroid lipoadenoma was defined as a single adenoma with more than 50% fat on histologic examination in conjunction with primary hyperparathyroidism and resolution of hypercalcemia postoperatively. Patients who fulfilled the diagnostic criteria were identified from the surgical pathology files of the Mayo Clinic.
  
  
  RESULTS
  Five cases of parathyroid lipoadenomas, including 1 oxyphil lipoadenoma, were identified during the period from 1971 to 2001. The clinical picture of the study subjects resembled that of a typical patient with primary hyperparathyroidism. Parathyroid lipoadenomas were identified in 3 women (60%) and 2 men (40%), and only 1 patient presented with possible hypercalcemia-related symptoms of nephrolithiasis and hip fracture, leading to diagnosis. The mean serum calcium concentration was 11.1 mg/dL. Preoperatively, all study subjects had elevation of serum parathyroid hormone levels. Two of 3 patients (67%) had the tumor identified preoperatively by neck ultrasonography.
  
  
  CONCLUSIONS
  A parathyroid lipoadenoma is a rare cause of primary hyperparathyroidism. The clinical features of this pathologic entity are similar to those of the more common pathologic variants of parathyroid disease associated with primary hyperparathyroidism.
authors.affiliation: Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic, College of Medicine, Rochester, Minnesota 55905, USA.
authors.forename: Lisa S
authors.initials: LS
authors.lastname: Chow
authors.forename: Lori A
authors.initials: LA
authors.lastname: Erickson
authors.forename: Haitham S
authors.initials: HS
authors.lastname: Abu-Lebdeh
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wermers
mesh_terms: D017667:Adipocytes / Q000648:ultrastructure; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology; D049950:Hyperparathyroidism, Primary / Q000209:etiology*; D008067:Lipoma / Q000150:complications* / Q000175:diagnosis / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000648:ultrastructure; D010281:Parathyroid Hormone / Q000097:blood; D010282:Parathyroid Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000473:pathology
chemical_list: D010281:Parathyroid Hormone