OUTLINE: This is an open-label, multicenter, dose-escalation study of lurtotecan liposome. Patients receive cisplatin IV over 1 hour followed by lurtotecan liposome IV over 30 minutes on days 1-3. Treatment repeats every 3 weeks in the absence of disease progression or unacceptable toxicity. Once the total dose of cisplatin is reached, patients receive lurtotecan liposome alone. Patients achieving complete response (CR) continue therapy for 2 courses after documentation of confirmed CR. Patients achieving partial response (PR) continue therapy until progression or for 2 courses after documentation of stable PR. Patients with stable disease continue therapy for a maximum of 6 courses. Cohorts of 3-6 patients receive escalating doses of lurtotecan liposome until the maximum tolerated dose (MTD) is reached. The MTD is defined as the dose at which at least 2 of 6 patients experience dose-limiting toxicity. Once the MTD is determined, up to 10 patients with previously untreated solid tumors are treated at the recommended phase II dose (1 dose below the MTD). Patients are followed at 4 weeks and then every 3 months for 1 year.