title: Location of abnormal parathyroid glands: lessons from 810 parathyroidectomies.
abstract: Primary hyperparathyroidism (pHPT) is commonly treated with targeted parathyroidectomy (PTX) guided by preoperative imaging and intraoperative parathormone monitoring. Despite advanced imaging techniques, failure of parathyroid localization still occurs. This study determines the anatomical distribution of single abnormal parathyroid glands, which may help direct the surgeon in PTX when preoperative localization is unsuccessful.
  
  
  
  A retrospective review of prospectively collected data of 810 patients with pHPT who underwent initial PTX at a tertiary medical center was performed. All patients had biochemically confirmed pHPT and single-gland disease. Abnormal parathyroid gland localization was determined at time of operation, correlated with operative and pathology reports, and confirmed by operative success defined as eucalcemia for ≥6 mo after PTX. Patients with multiple endocrine neoplasia, secondary, tertiary, or familial hyperparathyroidism, multiglandular disease, parathyroid cancer, and ectopic glands were excluded. Data were analyzed by chi-square and Z-test analyses.
  
  
  
  Among 810 patients who underwent PTX for pHPT, single abnormal parathyroid glands were unequally distributed among the four eutopic locations (left superior, 15.7%; left inferior, 31.3%; right superior, 15.8%; right inferior, 37.2%; P < 0.01). Abnormal inferior parathyroid glands (68.5%) were significantly more common than abnormal superior glands (31.5%), respectively (P < 0.01). In men, the most common location for single abnormal parathyroid glands was the right inferior position (43.4%, P < 0.01). Overall, there was no significant difference in laterality.
  
  
  
  This large series of patients suggests that single eutopic abnormal parathyroid glands are more likely to be inferior. In men, moreover, if an abnormal parathyroid gland is not localized preoperatively, the right inferior location should be explored first. Nevertheless, successful PTX remains predicated on knowledge of parathyroid anatomy, experience, and judgment of the surgeon.
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida. Electronic address: melissa.lopinto@gmail.com.
authors.forename: Melissa
authors.initials: M
authors.lastname: LoPinto
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida.
authors.forename: Gustavo A
authors.initials: GA
authors.lastname: Rubio
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida.
authors.forename: Zahra F
authors.initials: ZF
authors.lastname: Khan
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida.
authors.forename: Tanaz M
authors.initials: TM
authors.lastname: Vaghaiwalla
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida.
authors.forename: Josefina C
authors.initials: JC
authors.lastname: Farra
authors.affiliation: Division of Surgical Endocrinology, DeWitt Daughtry Family Department of Surgery, University of Miami Leonard M. Miller School of Medicine, Miami, Florida.
authors.forename: John I
authors.initials: JI
authors.lastname: Lew
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000033:anatomy & histology* / Q000601:surgery; D016105:Parathyroidectomy; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: Negative parathyroid imaging; Parathyroid anatomy; Parathyroid gland localization; Parathyroidectomy; Primary hyperparathyroidism