Case 1 was a 69-year-old male with non-Hodgkin's large B- cell lymphoma. He died following seizures and respiratory depression while he was receiving chemotherapy. At autopsy brain oedema and a small nodular mass located in the right lateral ventricular wall were discovered.
Case 2 was a 38-year-old female presenting with headache. MR revealed a mass, approximately 2.5cm in diameter in the right lateral ventricle extending to the third ventricle. Both tumors were diagnosed as subependymoma.
Microscopically, a fibrillary background, cell clusters with small uniform nuclei and microcysts were the main histopathological characteristics. Microcysts contained slightly basophilic material stained with alcian blue pH2.5 and toluidine blue pH7. This material was interpreted as extracellular mucin.
Tumoral infiltration was positive for GFAP and S-100 protein. Ki-67 (MIB-l) proliferation index was lower than 1%. P53 was negative in both cases.
Keywords : Subependymoma, autopsy, lateral ventricle, mucin, p53