Clinical study of intracranial nongerminomatous germ cell tumors producing alpha-fetoprotein. We present six patients with intracranial nongerminomatous germ cell tumors that produced alpha-fetoprotein (AFP). Their ages ranged from 8 to 20 years (average, 11.5 years old); two were male and four were female. Four of the tumors originated in the pineal region and two in the suprachiasmatic region. One patient treated with only radiation therapy died within 3 months of admission as a result of intraperitoneal metastasis via a ventriculoperitoneal shunt. Another patient, treated with radiation therapy and intrathecal administration of neocarzinostatin, died after 12 months because of tumor progression and subarachnoid dissemination. Two patients who received radiation and combination therapy with cisplatin, vinblastine, and bleomycin died after 13 and 25 months. The remaining two patients treated with radiation therapy and adjuvant chemotherapy (cisplatin and etoposide) are now alive without recurrence after 16 and 19 months from admission. Adjuvant chemotherapy with cisplatin and etoposide appears to be efficacious in the treatment of intracranial nongerminomatous germ cell tumor. 