Intracranial yolk sac tumor in a patient with Down syndrome.

The authors report a rare case of intracranial yolk sac tumor in a 13-year-old boy with Down syndrome who presented with left hemiparesis. Admission MR imaging revealed a tumor in the right basal ganglia. Serum α-fetoprotein was markedly elevated. Yolk sac tumor was diagnosed radiologically and serologically. The standard therapy for intracranial yolk sac tumor is platinum-based chemotherapy with concomitant radiotherapy. However, the authors used reduced-dose chemotherapy and asynchronized radiotherapy because of the well-known low tolerance of patients with Down syndrome to chemotherapy. This treatment was successful with no complications. Blood cancers are frequently associated with Down syndrome, whereas solid tumors occur less frequently in these patients, and the risk of chemoradiotherapy is unclear. The results indicate that dose-reduction therapy can be effective for treatment of a brain tumor in a patient with Down syndrome.