Abstract

Gliosarcoma is a distinct disease entity that is characterized by a biphasic tissue pattern with alternating areas displaying glial and mesenchymal differentiation. The tumor in our case was a rare morphologic variant of gliosarcoma with components of anaplastic oligodendroglioma and unclassifiable spindle cells. Spindle cells showed CD34 and S-100 protein immunoreactivity, which was possibly related to peripheral nerve sheath differentiation. This unique feature has not been described previously and so this case expands the spectrum of possible divergent mesenchymal differentiation, and it lends support to pluripotential stem cells being the origin of this tumor.

• Keywords: Gliosarcoma;Anaplastic oligodendroglioma;CD34;S-100 protein;