title: Keratinic amyloidosis of the external auditory canal.
abstract: OBJECTIVE
  We present a rare case of keratinic amyloidosis of the external auditory canal. This is only the seventh case reported of localized cutaneous amyloidosis of the external auditory canal with no systemic symptoms.
  
  
  METHODS
  A 62-year-old man, who had complained of an itchy external auditory canal and left-side hearing loss, was referred to our hospital because of a bilateral external auditory canal mass.
  
  
  METHODS
  Biopsy of the external auditory canal mass suggested a diagnosis of amyloidosis. However, total systemic examination failed to identify any disease due to systemic amyloidosis. This led us to diagnose him with localized cutaneous amyloidosis of the external auditory canal.
  
  
  METHODS
  We follow up periodically with systemic examination and local observation.
  
  
  RESULTS
  Thirty months after the initial diagnosis, he remains in follow-up and has not shown any significant aggravation of the disease.
  
  
  CONCLUSIONS
  In previous cases, the chief complaints were itching sensations and pain in the external auditory canal as well as a sense of discomfort when wearing a hearing aid. This suggests that chronic stimulation and inflammation of the skin lining the external auditory canal induced amyloidosis.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan; Department of Otolaryngology, Japanese Red Cross Shizuoka Hospital, Shizuoka, Japan. Electronic address: wasano@a5.keio.jp.
authors.forename: Koichiro
authors.initials: K
authors.lastname: Wasano
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Saito
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Kanzaki
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Ogawa
mesh_terms: D028226:Amyloidosis, Familial / Q000000981:diagnostic imaging / Q000473:pathology*; D001706:Biopsy; D004424:Ear Canal / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012873:Skin Diseases, Genetic / Q000000981:diagnostic imaging / Q000473:pathology*
keywords: Cytokeratin; External auditory canal; Keratin amyloidosis; Local amyloidosis