title: Giant cell tumor of rib masquerading as thymoma: a diagnostic pitfall in needle core biopsy of the mediastinum.
abstract: Giant cell tumor of bone is rarely seen in the rib, where it may present as a mediastinal mass. The diagnosis of giant cell tumor of bone is generally straightforward by fine-needle aspiration or needle core biopsy, but sampling problems may lead to confusion with other neoplasms or inflammatory processes. Here, we report a case of giant cell tumor of rib presenting as a mediastinal mass in a 36-year-old man. Because of inadequate sampling and inaccurate clinical information, the tumor was initially mistaken for thymoma. When the mass failed to respond to conventional chemotherapy, additional tissue was obtained and a giant cell tumor was diagnosed. Consequently, definitive therapy was delayed. The case illustrates an important diagnostic pitfall in the biopsy of mediastinal masses.
authors.affiliation: Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA. kevolmar@yahoo.com
authors.forename: Keith E
authors.initials: KE
authors.lastname: Volmar
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Sporn
authors.forename: Eric M
authors.initials: EM
authors.lastname: Toloza
authors.forename: Salutario
authors.initials: S
authors.lastname: Martinez
authors.forename: Leslie G
authors.initials: LG
authors.lastname: Dodd
authors.forename: H Bill
authors.initials: HB
authors.lastname: Xie
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000032:analysis; D001707:Biopsy, Needle; D001859:Bone Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D002467:Cell Nucleus / Q000648:ultrastructure; D003131:Combined Modality Therapy; D003951:Diagnostic Errors; D004847:Epithelial Cells / Q000473:pathology; D018212:Giant Cell Tumor of Bone / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D015726:Giant Cells / Q000473:pathology; D006801:Humans; D008297:Male; D008479:Mediastinal Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000532:radiotherapy / Q000601:surgery; D012074:Remission Induction; D012272:Ribs / Q000473:pathology* / Q000601:surgery; D013945:Thymoma / Q000175:diagnosis*; D013953:Thymus Neoplasms / Q000175:diagnosis*
chemical_list: D014408:Biomarkers, Tumor