Brain Pathology Case of the Month - September 2003


CLINICAL HISTORY:

The patient is a 79-year-old woman. Her chief complaints were headache, memory changes and sleep disturbance for 4 months. She had fallen down when she tried to stand up after waking up during the night one week prior to admission. Her family took her to the local hospital. Computed tomography and magnetic resonance image showed a large cystic mass in the right frontal lobe with heterogenicity and an enhancing border.

Her past medical history was significant for complete excision of a right parafalcine meningioma 10 years prior to admission. She had breast cancer (unknown histiologic type), treated by a left mastectomy and had been on tamoxifen for two years.

The patient underwent a craniotomy. Intraoperatively, the tumor was cystic and partially solid. The solid portion of the tumor was resected and the tissue was submitted to the Department of Pathology for frozen and permanent sections.

MICROSCOPIC EXAMINATION:

Microscopic examination of cytological imprints demonstrated exfoliation of cohesive clusters of cells showing marked nuclear pleomorphism (Figure 1). In some areas, the cells appeared to be forming whorls, but neither definite intranuclear cytoplasmic inclusions nor psammoma bodies were present. No glandular formation was seen. Cryostat sections disclosed a great deal of freezing artefact, however, neoplastic tissue characterized by hypercellularity and nuclear pleomorphism was present.

Paraffin embedded sections showed a biphasic malignant neoplasm composed of dense spindle cell areas forming rudimentary whorls and fascicles (Figure 2 and 3) and other loose areas of clear glial differentiation with vascular proliferation and necrosis (Figure 4). The mitotic rate was very high and cellular atypia was marked. A reticulin stain demonstrated a reticulin network present in the areas of spindle cells (Figure 5). No reticulin network was appreciated in the gliomatous portion. Immunohistochemical studies showed strong GFAP immunoreactivity in loose areas (Figure 6). GFAP immunoreactivity was focally observed in dense areas in neoplastic glia cells but not in neoplastic spindle cells (Figure 7). There was strong immunoreactivity in the dense spindle areas with vimentin and minimal focal EMA. Cytokeratin was negative.

FINAL DIAGNOSIS


International Society of Neuropathology