title: Occult thyroid carcinoma manifested as a large mediastinal tumor.
abstract: The authors report a rare case of clinically occult thyroid carcinoma that initially manifested as a metastatic mediastinal tumor with tracheal stenosis. A curative operation was performed by complete removal of the tumor through a median sternotomy approach combined with resection of the tracheal invasion. Histopathological examination revealed transition of a well-differentiated papillary carcinoma into a poorly differentiated component in the lesion invading the trachea, which suggested that this transition might have rendered the tumor more aggressive, leading to tracheal invasion.
authors.affiliation: Department of Otolaryngology, Tokyo University Branch Hospital, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ishibashi
authors.forename: S
authors.initials: S
authors.lastname: Yoshimoto
authors.forename: R
authors.initials: R
authors.lastname: Tsunoda
authors.forename: T
authors.initials: T
authors.lastname: Fukaya
authors.forename: M
authors.initials: M
authors.lastname: Asai
mesh_terms: D000231:Adenocarcinoma, Papillary / Q000175:diagnosis* / Q000601:surgery; D000368:Aged; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008479:Mediastinal Neoplasms / Q000175:diagnosis*; D013964:Thyroid Neoplasms / Q000175:diagnosis* / Q000601:surgery; D014057:Tomography, X-Ray Computed; D014139:Tracheostomy