Autopsy revealed diffuse leptomeningeal oligodendrogliomatosis, including the leptomeninges of the right optic nerve, with an intramedullary spinal cord component. The left eye had an amelanotic 3.0 × 2.5 × 1.0-mm mass in the choroid posteriorly (Figure 1A). The tumor cells had lightly eosinophilic cytoplasm and were organized as cords, nests, and ducts in a myxoid stroma containing spindle cells (Figure 1B). Ducts were best seen in the sections immunostained for cytokeratin and S-100 protein (Figure 2A and B). Some of the tumor cells had clear cytoplasm. Approximately 95% of the cells were immunoreactive with the pancytokeratin antibody AE1/AE3 (Figure 2A), and all of the cells expressed cytokeratin 7 and S-100 protein (Figure 2B). Vimentin (Figure 2C) and calponin (Figure 2D) were expressed by about 60% of the tumor cells, mostly in the central region of the tumor; smooth muscle actin expression had a similar distribution. Near the center of the tumor there was expression of CD57 between tumor cells, but the tumor peripherally was devoid of staining. There was only focal staining for epithelial membrane antigen (1% of cells), and only 1 tumor cell was undergoing DNA synthesis as evidenced by nuclear staining for Ki-67 antigen. The tumor cells did not express cytokeratin 20, neuroendocrine markers (chromogranin, synaptophysin, and neuron-specific enolase), p63 protein, gross cystic disease fluid protein 15, CD10, CD30, CD56, renal cell carcinoma antigen, CDX2, thyroid transcription factor 1, glial fibrillary acidic protein, WT1 protein, placental alkaline phosphatase, or α-fetoprotein, and they did not react with a cocktail of HMB-45/MART-1 antibodies.