title: Parathyroid carcinoma, atypical parathyroid adenoma, or parathyromatosis?
abstract: BACKGROUND
  Parathyroid carcinoma, atypical parathyroid adenoma, and parathyromatosis can be differentiated relatively easily from typical parathyroid adenomas, but distinguishing them from each other is more difficult.
  
  
  METHODS
  A retrospective study of 28 consecutive patients with parathyroid carcinoma, 7 patients with atypical parathyroid adenoma, and 13 patients with parathyromatosis who were treated at the University of California at San Francisco Medical Center between 1966 and 2005 was performed. Patient demographics and clinical characteristics, indication for surgery, intraoperative findings, histopathologic characteristics, disease recurrence or persistence, site of invasion/metastases, and survival were compared in the 3 groups.
  
  
  RESULTS
  Parathyroid carcinoma (19 of 28 patients) and atypical adenoma (4 of 7 patients) were significantly more common in men, whereas parathyromatosis was more common in women (10 of 13 patients) (P = .02). A palpable neck mass and hoarseness were almost exclusively present in patients with parathyroid carcinoma. Prior to the first parathyroid surgery, patients with parathyroid carcinoma were found to have higher blood calcium levels (>/=14 mg/dL in 16 of 26 patients [62%]), whereas only 1 of 6 patients with atypical adenoma (17%) and no patients with parathyromatosis were found to have profound hypercalcemia (P < .01). Intraoperatively, patients with parathyroid carcinoma and atypical adenoma presented with single lesions, whereas patients with parathyromatosis had multiple small lesions. Histopathologic findings were well defined in parathyroid carcinoma, but some findings overlapped in the 3 tumors studied.
  
  
  CONCLUSIONS
  Patients with parathyroid carcinoma often differ from those with atypical parathyroid adenoma or parathyromatosis at the time of presentation because patients with parathyroid carcinoma have more profound hypercalcemia as well as invasive tumors. However, at times it is difficult to distinguish between these conditions both clinically and by final histologic examination.
authors.affiliation: Department of Surgery, University of California at San Francisco, San Francisco, California 94143-1674, USA.
authors.forename: Gustavo G
authors.initials: GG
authors.lastname: Fernandez-Ranvier
authors.forename: Elham
authors.initials: E
authors.lastname: Khanafshar
authors.forename: Kristin
authors.initials: K
authors.lastname: Jensen
authors.forename: Rasa
authors.initials: R
authors.lastname: Zarnegar
authors.forename: James
authors.initials: J
authors.lastname: Lee
authors.forename: Electron
authors.initials: E
authors.lastname: Kebebew
authors.forename: Quan-Yang
authors.initials: QY
authors.lastname: Duh
authors.forename: Orlo H
authors.initials: OH
authors.lastname: Clark
mesh_terms: D000236:Adenoma / Q000473:pathology* / Q000601:surgery; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D006961:Hyperparathyroidism / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D010282:Parathyroid Neoplasms / Q000473:pathology* / Q000601:surgery; D012008:Recurrence; D012189:Retrospective Studies; D016019:Survival Analysis