title: Congenital cutaneous fistula at the sternoclavicular joint - Not a dermoid fistula but the remnant of the fourth branchial (pharyngeal) cleft ?
abstract: OBJECTIVE
  A fourth branchial pouch remnant is well known as a pyriform sinus fistula. However, there has been no report of a fistula composed of the complete remnant of the fourth branchial apparatus. We experienced patients with a congenital lower neck cutaneous fistula which was thought to be the skin-side remnant of the fourth branchial cleft.
  
  
  METHODS
  Seven children were referred to our hospital from 2009 to 2015 for the treatment of a cutaneous fistula situated near the sternoclavicular joint. All of them were surgically resected and their pathological characteristics were examined. Clinical charts were retrospectively reviewed.
  
  
  RESULTS
  In six cases, the left side was affected. All cutaneous fistulas had a small skin orifice near the sternoclavicular joint and they were situated at the anterior edge of the sternocleidomastoid muscle. Abscess formation was seen in four cases. Surgical resection was performed at the age of 6 months to 9 years. These fistulas ran deep into the subcutaneous tissue and had a blind end. Pathological examination showed that the epithelial layer was mainly composed of a stratified squamous epithelium. In two cases the epithelium was composed of ciliated columnar epithelium. Recurrence has not been observed in any of the cases.
  
  
  CONCLUSIONS
  The seven cases had a common clinical feature and were a definite clinical entity. Judging from the characteristics of our cases and the previous literature, we concluded that this lower neck cutaneous fistula was most likely a congenital skin-side remnant of the fourth branchial cleft.
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Michinobu
authors.initials: M
authors.lastname: Ohno
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan. Electronic address: kanamori-y@ncchd.go.jp.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kanamori
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Tomonaga
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Misato
authors.initials: M
authors.lastname: Migita
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Toshiko
authors.initials: T
authors.lastname: Takezoe
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Watanabe
authors.affiliation: Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Fuchimoto
authors.affiliation: Department of Pathology, National Center for Child Health and Development, 2-10-1 Okura Setagaya-ku, Tokyo 157-8535, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Matsuoka
mesh_terms: D000038:Abscess / Q000209:etiology*; D001934:Branchial Region / Q000002:abnormalities; D002648:Child; D002675:Child, Preschool; D017577:Cutaneous Fistula / Q000151:congenital* / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009333:Neck; D009334:Neck Muscles; D012189:Retrospective Studies
keywords: Cutaneous fistula; Fourth branchial cleft; Pyriform sinus fistula