title: An intracranial malignant solitary fibrous tumor.
abstract: Intracranial malignant solitary fibrous tumor (SFT) is very rare. It was identified in a 39-year-old female patient who underwent malignant transformation over 6 months. MRI revealed an 8 × 5 × 6 cm mass with heterogenous strong enhancement in the left occipital lobe. Histologic findings and immunophenotype (positive for CD34, bcl-2 and vimentin, and negative for epithelial membrane antigen or S100 protein) of the primary tumor were typical of SFT. However, there was a focal area (<10% of tumor volume) showing hypercellularity, nuclear pleomorphism and increased Ki-67 labeling index (LI) of 10% (average, 1%). At the second operation, the recurrent tumor revealed full-blown histologic features of malignant SFT, such as infiltrative brain invasion, marked nuclear pleomorphism, frequent mitotic figures (15/10 high power fields), and high Ki-67 LI (25%). The presence of atypical histologic finding or increased Ki-67 LI in the typical SFT, although it is focal, needs to be mentioned in the diagnosis and also may require more aggressive surgical management.
authors.affiliation: Department of Neurosurgery, Ilsan Baek Hospital, College of Medicine, Inje University, Goyang-Si, Gyeonggi-Do, Republic of Korea. cychoi@paik.ac.kr
authors.forename: Chan-Young
authors.initials: CY
authors.lastname: Choi
authors.forename: Seong-Rok
authors.initials: SR
authors.lastname: Han
authors.forename: Gi-Taek
authors.initials: GT
authors.lastname: Yee
authors.forename: Mee
authors.initials: M
authors.lastname: Joo
mesh_terms: D000328:Adult; D001932:Brain Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging; D009364:Neoplasm Recurrence, Local / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D054364:Solitary Fibrous Tumors / Q000378:metabolism / Q000473:pathology* / Q000601:surgery