OBJECTIVES: I. Determine the maximum tolerated doses and sequence of topotecan and ifosfamide that can be administered daily for 3 days on an every 4 week schedule in patients with refractory solid tumors. II. Evaluate toxicity of topotecan and ifosfamide when administered on this schedule in this patient population. III. Evaluate the pharmacokinetics related to sequencing of topotecan and ifosfamide and the more efficacious, less toxic schedule of treatment. IV. Assess the evidence of antineoplastic activity for this combination of agents.