Carcinoma of the choroid plexus is an extremely rare disease with a particularly virulent course. A case is reported in the left lateral ventricle of a young woman who is well 1 year after total excision of the tumor. The four previously reported patients with this disease who did well (two males and two females) were all children. Three of the four were treated with surgery followed by radiotherapy, and one with surgery alone. Although it appears possible that gross total removal may be curative, radiation therapy is suggested because of the distinct possibility that even the least aggressive-appearing lesions may degenerate and become rapidly fatal. Chemotherapy, although not used in any of the cases reported, is suggested as a possible adjunct in the treatment of this disease.