Solitary Fibrous Tumor : Histology

Histologic Features: Solitary fibrous tumors are composed of round or spindle cells arranged haphazardly (patternless pattern) or in short, intersecting fascicles around a rich vascular network. Some cases show vague storiform pattern. The tumor cells lack cytologic atypia and have moderate amount of eosinophilic cytoplasm with indistinct borders. Mitotic activity is not increased.