✓ Antitumor activity against intracranial malignant teratoma by combination chemotherapy with cisplatin and etoposide was evaluated in experimental and clinical studies. A human teratoma cell line (Tera 2) was exposed in vitro to cisplatin and/or etoposide, after which cell growth inhibition and alterations of deoxyribonucleic acid (DNA) histograms were observed. The results indicated that a synergistic cytotoxic effect was achieved by use of both agents in combination. Four cases of recurrent intracranial germ-cell tumor (three malignant teratomas and one germinoma) were treated with cisplatin and etoposide. With this combinationtherapy, regression of the tumor was observed in all four cases (three complete and one partial), for a total response rate of 100%. During a follow-up period of 9 to 22 months, no recurrence or progression has been noted in three of these cases.