title: Sinonasal inverted papilloma: narrative review.
abstract: BACKGROUND
  Sinonasal inverted papilloma is a benign condition with the potential for recurrence and malignant change. Over the past few decades, numerous studies and reviews have addressed different aspects of this condition.
  
  
  OBJECTIVE
  To amalgamate the current literature on inverted papilloma, in order to review the evidence and consider the gaps in current knowledge.
  
  
  METHODS
  Retrospective, narrative review.
  
  
  RESULTS
  The reported incidence of inverted papilloma varies between centres and is affected by selection bias. The exact aetiology of inverted papilloma is not fully understood. Currently, there is no reliable histological or biological marker to predict the probability of recurrence or malignant transformation. There is no universally accepted staging system available for sinonasal inverted papilloma. Complete surgical removal of the tumour is the mainstay of treatment, but the method of choice depends on the extent of the disease, the skill of the surgeon and the technology available.
  
  
  CONCLUSIONS
  In order to compare different studies and to enable meta-analysis of the literature, there should be a universally accepted staging and classification system for sinonasal inverted papilloma. Further research on the aetiology of sinonasal inverted papilloma, and on biological markers for its recurrence and malignant transformation, is required. To enable meaningful future research, we would encourage multicentre participation with a consensus on management.
authors.affiliation: Department of Otolaryngology/Head and Neck Surgery, Freeman Hospital, Newcastle upon Tyne, UK. sssanari@yahoo.co.uk
authors.forename: S
authors.initials: S
authors.lastname: Anari
authors.forename: S
authors.initials: S
authors.lastname: Carrie
mesh_terms: D006801:Humans; D009296:Nasal Cavity; D018308:Papilloma, Inverted / Q000473:pathology*; D010255:Paranasal Sinus Neoplasms / Q000473:pathology*; D012008:Recurrence; D012189:Retrospective Studies