title: Septochoanal polyp with osseous metaplasia: a case report.
abstract: BACKGROUND
  Polyps originating from the posterior septum with choanal extension, also known as "septochoanal polyps," are uncommon, and septochoanal polyps with central calcification are extremely rare. We report the second case of septochoanal polyps with central calcification in the English literature.
  
  
  METHODS
  A 55-year-old Thai woman presented with a progressive left-side nasal obstruction. An examination of her nose revealed an irregular lobulated mass, yellow in color, with a smooth surface that arose from her posterior nasal septum and extended down to her nasopharynx. Computed tomography revealed a large choanal mass with a central ossified structure. A punch biopsy was performed and microscopic examination showed an inflammatory polyp. The mass was removed using an endoscopic surgery technique, and the histology of this lesion confirmed a typical presentation of choanal polyps.
  
  
  CONCLUSIONS
  Although septochoanal polyps with osseous metaplasia are known to be very rare, physicians should be aware of them and include them in the differential diagnosis of choanal mass with central calcification lesions.
authors.affiliation: Department of Otolaryngology Head and Neck Surgery, Prince of Songkla University, Songkhla, 90110, Thailand. arrm012@gmail.com.
authors.forename: Chakapan
authors.initials: C
authors.lastname: Promsopa
mesh_terms: D005260:Female; D006801:Humans; D008679:Metaplasia; D008875:Middle Aged; D015508:Nasal Obstruction / Q000209:etiology; D009298:Nasal Polyps / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology; D009300:Nasal Septum / Q000000981:diagnostic imaging* / Q000473:pathology; D009305:Nasopharynx / Q000000981:diagnostic imaging* / Q000473:pathology; D009999:Ossification, Heterotopic / Q000150:complications / Q000000981:diagnostic imaging* / Q000473:pathology; D014057:Tomography, X-Ray Computed
keywords: Calcification; Choanal; Osseous metaplasia; Polyp; Septochoanal