title: Sinonasal hybrid tumour involving the anterior skull base.
abstract: OBJECTIVE
  We report a rare case of sinonasal hybrid tumour within an inverted papilloma.
  
  
  METHODS
  The patient's case history and course of management are presented. The relevant medical literature are reviewed and discussed.
  
  
  RESULTS
  A 60-year-old man presented with unilateral nasal obstruction associated with anosmia. An ENT examination revealed a unilateral, left nasal mass. A provisional diagnosis of inverted papilloma was made. The patient underwent a transnasal endoscopic excision of the tumour, which was unfortunately complicated by a cerebrospinal fluid leak. Further treatment of this patient is described. We highlight the features of associated malignancy in inverted papilloma, and the importance of thorough histopathological examination of tissue specimens.
  
  
  CONCLUSIONS
  Treatment of inverted papilloma with limited involvement of the skull base can be successfully achieved by endoscopic excision. A high index of clinical suspicion, together with meticulous histopathological examination, will enable diagnosis of associated malignancy. This will ensure that appropriate adjuvant treatment is given, resulting in a good clinical outcome.
authors.affiliation: Department of Otorhinolaryngology - Head & Neck Surgery, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia. mazitaami@yahoo.com
authors.forename: A
authors.initials: A
authors.lastname: Mazita
authors.forename: B S
authors.initials: BS
authors.lastname: Gendeh
authors.forename: A I
authors.initials: AI
authors.lastname: Zainal
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000628:therapy; D018289:Carcinoma, Verrucous / Q000175:diagnosis / Q000628:therapy; D004724:Endoscopy; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015508:Nasal Obstruction / Q000209:etiology; D009378:Neoplasms, Multiple Primary / Q000175:diagnosis / Q000628:therapy*; D000857:Olfaction Disorders / Q000209:etiology; D018308:Papilloma, Inverted / Q000175:diagnosis / Q000628:therapy; D010255:Paranasal Sinus Neoplasms / Q000175:diagnosis / Q000628:therapy; D012086:Reoperation; D019291:Skull Base; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome