Brain

50-year-old female with headache, right hemiparesis, and a left temporal lobe neoplasm.

Procedure: Craniotomy, removal of neoplasm from left temporal lobe.

Gross: The specimen consists of irregu

This malignant neoplasm is composed of large neoplastic lymphocytes. CD-45, CD-20, and CD-45RO are positive. CD-3 is negative.

The EMA stain is focally positive. The Ki-67 stain shows a low proliferative rate (<1%).

The tumor consists of well-differentiated keratinizing squamous epithelium in a papillary architecture.

The tumor is predominantly the tall cell variant of papillary thyroid carcinoma. There is no evidence of a follicular carcinoma component in this specimen.

Since the gangliocytes are dysplastic and largely limited to the granular layer of the cerebellum, the lesion is compatible with Lhermitte-Duclos Disease.

Sections show a pilocytic glial neoplasm with sparse Rosenthal fibers and more frequent eosinophilic granular bodies.