title: Pleomorphic adenoma presenting with conductive hearing loss in the ear canal: a case report and review of the literature.
abstract: BACKGROUND
  Pleomorphic adenoma accounts for 65 percent of all salivary gland tumors. It has been identified in several anatomical regions, but pleomorphic adenoma arising in the ear canal, first described in 1951, is extremely rare.
  
  
  METHODS
  A 40-year-old Japanese man's left ear canal was obstructed by a pleomorphic adenoma that caused mild conductive hearing loss. The tumor was resected and he remains disease-free two years after surgery.
  
  
  CONCLUSIONS
  Pleomorphic adenoma usually arises from a major and minor salivary gland, but pleomorphic adenoma of the ear canal is derived from the ceruminous gland. We discuss the present case and 37 other case reports in our effort to clarify the clinical features and the course of pleomorphic adenoma in the ear canal.
authors.affiliation: Department of Otolaryngology, Tokyo Medical and Dental University, Bunkyo-ku, Yushima 1-5-45, Tokyo 113-8519, Japan. maruyamaoto@gmail.com.
authors.forename: Ayako
authors.initials: A
authors.lastname: Maruyama
authors.forename: Takao
authors.initials: T
authors.lastname: Tokumaru
authors.forename: Ken
authors.initials: K
authors.lastname: Kitamura
mesh_terms: D008949:Adenoma, Pleomorphic / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D000328:Adult; D004424:Ear Canal / Q000601:surgery; D004428:Ear Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000601:surgery; D006314:Hearing Loss, Conductive / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D008297:Male; D012468:Salivary Gland Neoplasms / Q000150:complications* / Q000175:diagnosis / Q000601:surgery