title: Esthesioneuroblastoma recurrence presenting as a syndrome of inappropriate antidiuretic hormone secretion.
abstract: BACKGROUND
  Esthesioneuroblastoma is an uncommon intranasal tumor. These neuroendocrine neoplasms are rarely associated with excess hormone syndromes, and only nine cases of inappropriate antidiuretic hormone syndrome (SIADH) secondary to an esthesioneuroblastoma have been described. In all these cases, electrolyte abnormalities were seen when the tumor initially developed. We report a unique case of esthesioneuroblastoma recurrence manifesting as SIADH as the solely presenting feature.
  
  
  RESULTS
  A 34-year-old woman was referred to us for evaluation for hyponatremia. She had undergone resection of an esthesioneuroblastoma at age 18 with radiotherapy. The patient had undergone annual CT of the nasal area and was considered to be disease free. The study of the hyponatremia was consistent with a SIADH, and MRI revealed an intranasal mass. The resection of the tumor reversed the hyponatremia, and pathologic analysis revealed a recurrence of esthesioneuroblastoma.
  
  
  CONCLUSIONS
  Biochemical analysis should be performed in the follow-up of patients with esthesioneuroblastoma. In our case, the biochemical abnormality led to the diagnosis of the recurrence.
authors.affiliation: Endocrinology Department, Hospital Universitario Insular de Gran Canaria, Las Palmas de Gran Canaria University, Avda. Marítima del Sur s/n, 35016. Las Palmas de Gran Canaria, Spain. yloppla@yahoo.com
authors.forename: Y López
authors.initials: YL
authors.lastname: Plasencia
authors.forename: M Boronat
authors.initials: MB
authors.lastname: Cortés
authors.forename: D Marrero
authors.initials: DM
authors.lastname: Arencibia
authors.forename: T Montenegro
authors.initials: TM
authors.lastname: Dámaso
authors.forename: I Lisner
authors.initials: IL
authors.lastname: Contreras
authors.forename: A Ojeda
authors.initials: AO
authors.lastname: Pino
authors.forename: A Carrillo
authors.initials: AC
authors.lastname: Domínguez
authors.forename: F La Roche
authors.initials: FL
authors.lastname: Brier
authors.forename: Y García
authors.initials: YG
authors.lastname: Delgado
authors.forename: F J Nóvoa
authors.initials: FJ
authors.lastname: Mogollón
mesh_terms: D000328:Adult; D018304:Esthesioneuroblastoma, Olfactory / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D005260:Female; D006801:Humans; D007177:Inappropriate ADH Syndrome / Q000209:etiology*; D009296:Nasal Cavity; D009364:Neoplasm Recurrence, Local / Q000150:complications* / Q000175:diagnosis / Q000628:therapy; D009669:Nose Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000628:therapy