title: Magnetic resonance imaging of pleomorphic adenoma arising from the external auditory canal.
abstract: Pleomorphic adenoma arising from the external auditory canal is a very rare neoplasm, and there has been no report on magnetic resonance (MR) imaging of pleomorphic adenoma of the external auditory canal. We report here a case of 65-year-old male with this tumour, measuring 12 mm in a diameter. Histopathology was confirmed from the specimen obtained at the surgical excision. MR revealed that the tumour had a well-defined margin showing hypointensity on T1-weighted images and hyperintensity on T2-weighted images relative to the parotid gland. The tumour was well enhanced by contrast material. No invasion to the surrounding tissue was observed. These MR findings were compatible with pleomorphic adenoma of the salivary gland origin. In treating pleomorphic adenoma of the external auditory canal, complete surgical excision is essential for the prevention of recurrence. It can be concluded that MR imaging is helpful for making a differential diagnosis of external auditory canal tumours and selection of adequate treatment.
authors.affiliation: Department of Otolaryngology, Osaka University Medical School, Suita, Osaka, Japan.
authors.forename: Chisako
authors.initials: C
authors.lastname: Masumura
authors.forename: Arata
authors.initials: A
authors.lastname: Horii
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Mishiro
authors.forename: Hidenori
authors.initials: H
authors.lastname: Inohara
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kitahara
authors.forename: Shodayu
authors.initials: S
authors.lastname: Takashima
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kubo
mesh_terms: D008949:Adenoma, Pleomorphic / Q000175:diagnosis*; D003937:Diagnosis, Differential; D004424:Ear Canal / Q000473:pathology*; D004428:Ear Neoplasms / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged