[Malignant teratoid medulloepithelioma of the ciliary body and glial fibrillary acidic protein. Clinical, histochemical and immunohistochemical findings].

In a four-year-old boy a malignant teratoid medulloepithelioma of the ciliary body was removed by means of an 11.0 X 11.0 mm "block excision". Two years later the patients visual acuity was 0.6. The lesion originates in the nonpigmented ciliary epithelium, extending along the lens equator to the pupillary zone and through the iris stroma into the anterior chamber. The tumor shows tubular structures with hyaluronic acid, "retinal rosettes", and areas with ganglion and GFAP-positive glial cells. The immunohistochemical demonstration of the glial fibrillary acidic protein is also of diagnostic value for the classification of tumors of the nonpigmented ciliary epithelium.