Primary gliosarcoma: key clinical and pathologic distinctions from glioblastoma with implications as a unique oncologic entity

Abstract

This report presents the historical experience, clinical presentation, treatment, prognosis, and pathogenesis of gliosarcoma described to date in the English literature. PubMed query of term "gliosarcoma" was performed, followed by a rigorous review of cited literature. Articles selected for analysis included: (1) case reports of gliosarcoma, (2) review articles of gliosarcoma, and (3) studies of the pathogenesis or genetics of gliosarcoma in humans. Our review identified 219 cases of gliosarcoma in 34 reports and eight articles addressing the pathogenesis. Survival in larger series ranged 4-11.5 months. Features unique to gliosarcoma compared to glioblastoma (GBM) include their temporal lobe predilection, potential to appear similar to a meningioma at surgery, repeated reports of extracranial metastases, and infrequency of EGFR mutations. Published experience is limited to small case series, and the pathogenesis remains unclear. Clinical and pathologic characteristics distinct from GBM suggest that they may warrant specific treatment, separate from conventional GBM therapy.

Fig. 1

Histology of gliosarcoma. a 200×. Immunohistochemical staining for vascular marker CD31, demonstrating focal perinuclear positivity in many of the tumor cells. Positive staining vascular endothelium serves as internal control. b 200×. Focal strong membranous staining of tumor cells with CD34 antibody. Positive staining within vascular endothelium serves as internal control. c 200×. Focal weak cytoplasmic staining with GFAP antibody in tumor cells. This suggests a glial origin. d Hematoxylin and eosin stain, 200×. Vascular endothelial proliferation and myxoid and chondromatous area in a gliosarcoma. The tumor cells show focal myxoid change and epithelioid morphology

Fig. 2

Morphology of gliosarcoma a Smear preparation, hematoxylin and eosin stain, 100×. Portion of the tumor showing sarcomatous, spindle morphology. Other potential differentiation includes osseous, vascular, skeletal muscle, and adipose phenotypes. b GFAP, 100×. The sarcomatous component is GFAP negative c 400×. The basement membrane is highlighted by Laidlaw Reticulin impregnation in the sarcomatous component of the tumor. Reticulin shows thick uniform atypical appearance

Fig. 3

Neuroimaging of a gliosarcoma before surgery. Gadolinium-enhanced T1-weighted axial images of the patient’s left sided temporal lobe gliosarcoma