title: An unusual case of primary hyperparathyroidism with profoundly elevated parathyroid hormone levels.
abstract: OBJECTIVE
  To report the case of a man who presented with profoundly elevated parathyroid hormone levels in the setting of hypercalcemia, a palpable neck mass, renal disease, and metabolic bone disease.
  
  
  METHODS
  We describe the clinical, imaging, and laboratory findings of the patient, including results from genetic testing of the CDC73 gene (HRPT2), and review the relevant literature.
  
  
  RESULTS
  A 28-year-old man with a history of childhood abdominal neuroblastoma treated with chemotherapy and field radiation therapy presented with a 2-week history of persistent left scapular pain and swelling. He had a freely mobile, 1-cm, homogeneous, nontender, firm nodule in the right anterior neck. Parathyroid hormone concentration at hospital admission was 1127 pg/mL. Single-photon emission computed tomography after intravenous administration of technetium Tc 99m-labeled sestamibi revealed an intense focus of abnormal radiotracer uptake on early and delayed images in the right anterior inferior neck. Computed tomography imaging of the chest and neck revealed a 1.9-cm, smooth, calcified nodule posterior to the right lobe of the thyroid gland and diffusely osteopenic bones with trabecular resorption and numerous scattered lucent regions consistent with brown tumors. On bilateral neck exploration, a right inferior parathyroid mass and the left superior parathyroid gland were excised. The remaining 2 parathyroid glands were identified intraoperatively and appeared normal. Genetic testing of the CDC73 gene did not detect germline mutations.
  
  
  CONCLUSIONS
  This case highlights the overlap between the clinical findings seen in primary hyperparathyroidism and parathyroid carcinoma. Enhanced understanding of the genetic and molecular bases of primary hyperparathyroidism and parathyroid carcinoma should aid in the diagnosis of these diseases and the care of affected patients.
authors.affiliation: Diabetes Unit, Massachusetts General Hospital, Boston, MA 02114, USA.
authors.forename: Allan F
authors.initials: AF
authors.lastname: Moore
authors.forename: Tamara L
authors.initials: TL
authors.lastname: Wexler
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Yung
authors.forename: Joshua
authors.initials: J
authors.lastname: Kish
authors.forename: Mykol
authors.initials: M
authors.lastname: Larvie
authors.forename: Kelly
authors.initials: K
authors.lastname: Lauter
authors.forename: Andrew
authors.initials: A
authors.lastname: Arnold
authors.forename: Joel S
authors.initials: JS
authors.lastname: Finkelstein
authors.forename: Sherri M
authors.initials: SM
authors.lastname: Burnett-Bowie
mesh_terms: D000328:Adult; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008297:Male; D010281:Parathyroid Hormone / Q000378:metabolism*; D010282:Parathyroid Neoplasms / Q000378:metabolism / Q000473:pathology; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon; D025521:Tumor Suppressor Proteins / Q000235:genetics
chemical_list: C454900:CDC73 protein, human; D010281:Parathyroid Hormone; D025521:Tumor Suppressor Proteins; D017256:Technetium Tc 99m Sestamibi