[A teratoid malignant medulloepithelioma of the optic nerve].

Medulloepithelioma is a clinically uncommon tumor originated from nervous system, often occurred in central nerve system and ciliary body, and malignant medulloepithelioma of the optic nerve is far rarer. So far, there has been no case report in China. It may be clinically misdiagnosed because it resembles glioma at the early stage of the disease. We reported a boy with a tumor in his right eye at age of 3.8 years, which was shown by biopsy of the partial tumor that there were some obviously heteromorphous neoplastic cells, karyokinesis, and moreover, some neoplastic cells differentiated into cartilage cells, gradually formed into hyaline cartilage islands and the expressions of NSE and S-100 were positive. Teratoid malignant medulloepithelioma of optic nerve was made pathologically.