title: Papillary carcinoma with extensive squamous metaplasia arising from thyroglossal duct cyst in an 11-year-old girl: significance of differentiation from squamous cell carcinoma: a case report.
abstract: We report a case of papillary carcinoma (PC) with extensive squamous metaplasia arising from a thyroglossal duct cyst (TDC) that required differential diagnosis from squamous cell carcinoma (SCC). An 11-year-old Japanese girl presented with a 9-month history of an anterior-midline neck mass that was clinically diagnosed as TDC. Open neck biopsy revealed nested proliferation of atypical squamous cells within the cystic structures, and SCC arising from TDC was initially suspected. Further examination, however, including immunohistochemistry, revealed the tumor to be of thyroid cell origin. The patient underwent wide local resection of the thyroglossal duct carcinoma by Sistrunk procedure and cervical lymph node dissection. Microscopically, the diagnosis was of PC with extensive squamous metaplasia and metastasis to the medial submandibular lymph node. Distinction of squamous metaplasia in PC from SCC is sometimes difficult, but has a significant effect on postoperative management.
authors.affiliation: Division of Pathology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan. Electronic address: gomikiyoshi@yahoo.co.jp.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Gomi
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Kitagawa
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Usui
authors.affiliation: Division of Pathology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Mio
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Division of Pathology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Yoshida
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Hirata
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Taiichiro
authors.initials: T
authors.lastname: Kosaka
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Honda
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Take
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Shinkai
authors.affiliation: Division of Radiology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Ayako
authors.initials: A
authors.lastname: Shishikura
authors.affiliation: Division of Radiology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Aida
authors.affiliation: Division of Surgery, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Youkatsu
authors.initials: Y
authors.lastname: Ohhama
authors.affiliation: Division of Pathology, Kanagawa Children's Medical Center, Yokohama City, Kanagawa Prefecture 232-8555, Japan.
authors.forename: Yukichi
authors.initials: Y
authors.lastname: Tanaka
mesh_terms: D001706:Biopsy; D002291:Carcinoma, Papillary / Q000175:diagnosis* / Q000601:surgery; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D002454:Cell Differentiation; D002648:Child; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008679:Metaplasia; D013955:Thyroglossal Cyst / Q000175:diagnosis* / Q000601:surgery; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000601:surgery; D013965:Thyroidectomy; D014057:Tomography, X-Ray Computed