One hundred thirty-eight pediatric patients have received treatment for malignant solid tumors with ifosfamide with mesna, and 71 have received a combination with ifosfamide/carboplatin/etoposide (ICE). Responses were obtained in many types of pediatric tumors, yet comparison of responses was not possible because of inadequate numbers of tumors of differing histiotypes. Comparison of results between patients with all tumors treated with ifosfamide or ICE indicated that there was a higher response rate for patients treated with ICE, with an estimated odds ratio of 2.74 (95% C.I. 1.45-5.179). Excluding patients without prior chemotherapy and radiotherapy, the odds ratio for 2.801 (95% C.I. 1.45-5.4) suggests a similar result. There remain no guarantees that the more costly treatment with ICE, which requires cytokine support, will offer therapeutic benefits against resistant solid tumors.