title: Prognostic factors and staging systems in parathyroid cancer: a multicenter cohort study.
abstract: BACKGROUND
  Parathyroid carcinoma (PC) is an uncommon disease that generally is detected postoperatively and traditionally is associated with a poor prognosis. Our purpose was to evaluate treatment outcomes, prognostic factors, and usefulness of some proposed staging systems for this disease.
  
  
  METHODS
  A multicenter review of patients with surgically resected PC was performed, led by the Spanish Association of Surgery. All surgical units affiliated with its endocrine surgery section were invited to answer a questionnaire that collected several hospital-related, clinical, biochemical, operative, pathologic, and follow-up data. Their relationships with prognosis were assessed by both univariate and multivariate analysis, as well as the effectiveness of three staging systems for parathyroid carcinoma.
  
  
  RESULTS
  Of the 6,863 patients undergoing parathyroidectomy, 62 (0.9%) had PC. Of them, 12 (19.3%) died, in 5 cases (8%) because of disease, and 14 (22.6%) suffered recurrence, after a median follow-up of 55 months. The most predictive independent variables on tumor recurrence were intraoperative tumor rupture (hazard ratio [HR] 6.22; 95% confidence interval [CI] 1.19-32.36; P = .030); the presence of mitotic figures within tumor parenchyma cells (HR 4.76; 95% CI 1.24-18.21; P = .022); and allocation in class III according to Schulte differentiated staging classification (HR 5.23; 95% CI 1.41-19.31; P = .013). As to disease-specific survival, poor outcomes were associated with intraoperative tumor rupture (HR 58.71; 95% CI 2.39-1,439.96; P = .013) and distant recurrence (HR 38.74; 95% CI 3.44-435.62; P = .003).
  
  
  CONCLUSIONS
  In addition to factors associated with tumor histopathology and stage, prognosis of PC is greatly influenced by surgeon's performance, which emphasizes the importance of preoperative diagnosis.
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Virgen de las Nieves University Hospital, Granada, Spain. Electronic address: jevillarmo@yahoo.es.
authors.forename: Jesús
authors.initials: J
authors.lastname: Villar-del-Moral
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Virgen Macarena University Hospital, Sevilla, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Jiménez-García
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Complejo Hospitalario de Navarra, Pamplona, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Salvador-Egea
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Virgen del Rocio University Hospital, Sevilla, Spain.
authors.forename: Juan M
authors.initials: JM
authors.lastname: Martos-Martínez
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Meixoeiro Hospital, Vigo, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Nuño-Vázquez-Garza
authors.affiliation: Department of Surgery, Complejo Hospitalario de Jaen, Jaen, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: Serradilla-Martín
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Basurto University Hospital, Bilbao, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Gómez-Palacios
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Bellvitge University Hospital, Barcelona, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Moreno-Llorente
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Clinic University Hospital, Valencia, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Ortega-Serrano
authors.affiliation: Endocrine Surgery Unit, Department of Surgery, Cruces University Hospital, Baracaldo, Spain.
authors.forename: Aitor
authors.initials: A
authors.lastname: de la Quintana-Basarrate
mesh_terms: D000368:Aged; D002277:Carcinoma / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010280:Parathyroid Glands / Q000473:pathology*; D010282:Parathyroid Neoplasms / Q000453:epidemiology / Q000473:pathology* / Q000628:therapy; D011379:Prognosis; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D016896:Treatment Outcome