This patient had total body radiation for acute lymphocytic leukemia when a child.

These are radiation-induced meningiomas, which are more frequently multiple and have a very long latency.

The patient went on to have resection of the two largest left sided tumors. 

Histology

The paraffin sections show a variably hypercellular dural-based tumor.  Tumor cells are a mixture of epithelioid and spindle morphology and are arranged in diffuse sheets and loose fasciculi. In many areas, a chordoid appearance is also noted with solid aggregates and cords of epithelioid tumor cells dispersed within a myxomatous stroma.

Tumor cells show moderate nuclear pleomorphism and an occasional mitotic figure is identified (1/20 HPF). No areas of necrosis are seen. There is no brain invasion.

Immunohistochemistry shows strong nuclear staining in tumor cells for progesterone receptor (PgR) and strong membrane staining for epithelial membrane antigen (EMA). There is also moderate staining for  bcl-2 and patchy moderate staining for smooth muscle actin (SMA). No staining for CD34, ALK-1, desmin or pancytokeratin AE1/AE3 is seen in tumor cells.  

DIAGNOSIS: Chordoid meningioma (WHO grade II).