Malignant fibrous histiocytoma originating from the thymus.
A 63-year-old man with a history of acute coronary syndrome presented with anterior chest pain that had lasted more than 3 months. During treatment for acute myocardial infarction on admission, computed tomography (CT) was performed incidentally, revealing an anterior mediastinal tumor 28 mm in diameter. CT findings after 3 months demonstrated an anterior soft tissue mass involving the left brachiocephalic vein and showing rapid growth. Radical resection of the tumor with thymectomy was performed. Histological examination showed storiform-pleomorphic malignant fibrous histiocytoma (MFH) originating from the thymus, and Hassall's bodies were identified. Immunohistochemical staining showed tumor cells with positive results for vimentin and CD68. The Ki-67 index (MIB-1) was >50%, but other markers such as cytokeratin AE1/AE3, smooth muscle actin, S-100 protein, CD34, and CD45 were negative. Mediastinum MFH has been reported in 34 cases, but this appears to be a rare description of MFH originating from the thymus.
Imai
Kazuhiro
K
Division of Thoracic Surgery, Department of Surgery, Akita University School of Medicine, and Akita Kumiai General Hospital, 1-1-1 Hondo, Akita, 010-8543, Japan. karo@doc.med.akita-u.ac.jp
Saito
Hajime
H
Minamiya
Yoshihiro
Y
Hashimoto
Masaji
M
Kimura
Yoshihiko
Y
Ogawa
Jun-ichi
J
D016121:Brachiocephalic Veins / Q000473:pathology / Q000601:surgery; D051677:Histiocytoma, Malignant Fibrous / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D006801:Humans; D007150:Immunohistochemistry; D033162:Incidental Findings; D008297:Male; D008479:Mediastinal Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D018714:Radiotherapy, Adjuvant; D013934:Thymectomy; D013953:Thymus Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome