Figure 3

A panoramic view of the solitary fibrous tumor. (a) note the cellular proliferation of spindled cells, the dense collagen and the ‘stag horn’ vessels (H&E, x100); (b) The tumor cells surround a vascular component with a ‘stag horn’ appearance ((b) H&E, x150); (c) The tumor cells show a widespread immunoreactivity for CD34 (immunoperoxidase stain for CD34, x200); (d) The tumor cells exhibit a strong positivity for CD99 (immunoperoxidase stain for CD99, x200); (e) The tumor cells exhibit a diffuse staining for bcl-2 (immunoperoxidase stain for bcl-2, x200); (f) The tumor cells show a proliferation index to a maximum of about 10% of neoplastic cells (immunoperoxidase stain for Ki67/MIB-1, x150).