IFOSFAMIDE AND ETOPOSIDE IN THE TREATMENT OF ADVANCED SOFT-TISSUE SARCOMAS

Ifosfamide is an active chemotherapeutic agent in the treatment of sof t tissue sarcoma. This Phase II study attempted to evaluate the effica cy of the addition of etoposide to ifosfamide administered to patients with recurrent or metastatic soft tissue sarcoma. Treatment consisted of etoposide 100 mg/m(2), followed by ifosfamide 2.0 g/m(2), daily, f or 4 consecutive days. Mesna was administered for uroprotection. Cycle s were repeated at 21-day intervals or upon recovery from toxicity. Tw o partial responses were observed in 19 evaluable patients (response r ate 10.5%, 95% confidence interval, 7% to 14%). Response durations wer e brief at 2 and 6 months. In a subset of 10 patients with gastrointes tinal leiomyosarcoma, no responses were observed. Toxicity was general ly mild, consisting primarily of myelosuppression and controllable nau sea and emesis. No episodes of hematuria were observed. Overall surviv al for all eligible patients was 10 months (range: 0.2 to 34.7(+) mont hs). Etoposide, in this dose and schedule, failed to enhance the activ ity of ifosfamide in adult soft tissue sarcoma. Additionally, this exp erience and a review of the literature, suggest that ifosfamide has li ttle activity against gastrointestinal leiomyosarcomas. Continued effo rts are needed to identify novel agents with efficacy against these re sistant tumors.