- Clinical History
- Light Microscopy
- Electron Microscopy
- Diagnosis and Comment
Electron Microscopy
The patient was referred to another institution for treatment where the pathology material was re-reviewed and electron microscopy was performed on the biopsy tissues because of the disparity between cellularity of the lesion and relative absence of mitotic activity.
Ultrastructural examination showed atypical cells with nuclei ranging in shape from ovoid to crescent-shaped. Exceptionally long junctional complexes linked the tumor cells. In addition, many cells contained cytoplasmic lumina with microvilli and cilia (Fig 4).
The diagnosis was changed to ependymoma.
Fig 4. Electron micrograph, x4000. The neoplastic cells contained intracytoplasmic lumina containing microvilli (arrow). Long zipper-like cell-to-cell junctions connected adjacent neoplastic cells (arrowheads).