title: Medially originated inverted papilloma.
abstract: OBJECTIVE
  The objective of this study was to determine the characteristics of medially originated inverted papilloma (MOIP) and compare them with laterally originated inverted papilloma (LOIP).
  
  
  METHODS
  A retrospective review of the charts for a total of 83 patients with sinonasal inverted papilloma (IP) was conducted. Tumors originating from the nasal septum or the turbinates were categorized as MOIP, whereas tumors originating from the four sinuses were categorized as LOIP.
  
  
  RESULTS
  Twenty-eight (34%) and 55 (66%) cases were categorized as MOIP and LOIP. MOIP from the middle turbinate behaved more aggressively than LOIP from the ethmoid sinus (P = 0.009), but less aggressively than LOIP from the maxillary medial wall (P < 0.05). Radical procedures were implemented in 14 patients with LOIP, but not in any patients with MOIP (P = 0.002). The recurrence rates were comparable in both groups (P = 0.472).
  
  
  CONCLUSIONS
  The categorization of IP on the basis of tumor origin enabled a better surgical design and more accurate excision of the tumor. Although in some cases MOIP may behave more aggressively, radical procedures were indicated in only the late Krouse stage LOIP without compromising the recurrence rate.
authors.affiliation: Division of Rhinology, Department of Otolaryngology, Chang Gung Memorial Hospital, Chang Gung University, Kwei-Shan, Taoyuan, Taiwan.
authors.forename: Ta-Jen
authors.initials: TJ
authors.lastname: Lee
authors.forename: Chi-Che
authors.initials: CC
authors.lastname: Huang
authors.forename: Yi-Wei
authors.initials: YW
authors.lastname: Chen
authors.forename: Kai-Ping
authors.initials: KP
authors.lastname: Chang
authors.forename: Chia-Hsiang
authors.initials: CH
authors.lastname: Fu
authors.forename: Po-Hung
authors.initials: PH
authors.lastname: Chang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008444:Maxillary Sinus Neoplasms / Q000473:pathology / Q000601:surgery; D008875:Middle Aged; D013517:Otorhinolaryngologic Surgical Procedures; D018308:Papilloma, Inverted / Q000145:classification / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D010255:Paranasal Sinus Neoplasms / Q000145:classification / Q000175:diagnosis / Q000473:pathology / Q000601:surgery*; D014420:Turbinates / Q000473:pathology; D055815:Young Adult