Between November 1983 and November 1988, 60 patients with cerebral metastases arising from primary lung cancer were treated with chemotherapy. Thirty patients received a 5-day course of cisplatin (total dose: 200 mg/sq.m). The remaining 30 patients received VP 16 in doses of 250 mg/sq.m. administered 12-hourly by intravenous infusion over one hour (total dose: 1,500 mg/sq.m.). Twenty-seven percent of the patients who received cisplatin showed objective responses as assessed by computerized tomography; 10% had serious toxic reactions. Thirty percent of the patients who received VP 16 showed objective responses, but 43% had severe bone marrow aplasia resulting in a 33% death rate due to infection. The median survival of responders was 8 months in both treatment groups. The objective response rates as assessed by histology were 33% in patients with oat-cell carcinoma and 27% in patients with other histological types. VP 16 must be abandoned, being too toxic in high doses. High-dose cisplatin can be used in the treatment of cerebral metastases of lung cancer, side by side with radiotherapy.