Melanotic ganglioglioma of the pineal region.

A melanotic ganglioglioma was biopsied in the pineal region of a 12-month-old girl who preoperatively underwent a ventriculo-peritoneal shunt for hydrocephalus and postoperatively received radiotherapy. The tumor was subtotally excised when the girl was 7 years and 4 months of age. Histologically, it demonstrated mature neurons in disorganized clusters and in well-differentiated cerebrum-like tissue, rare binucleated neurons, glia similar to normal gray matter, and bands of fibrous tissue containing heavily pigmented cells. Ultrastructurally, melanosomes of stages I to IV were identified in the pigmented cells. An origin involving retinal differentiation of the primitive pineal gland was not supported; the tumor was negative for both retinal S-antigen (MAbA9-C6) and cellular retinal-binding protein (CRALBP). This report demonstrates the ability of a cerebral neoplasm to contain neurons, glia, and melanin-containing cells; all of which are neuroectodermally derived.