Ifosfamide with mesna uroprotection and etoposide: an effective regimen in the treatment of recurrent sarcomas and other tumors of children and young adults.

One hundred twenty-four children and young adults with recurrent tumors, predominantly sarcomas, were treated with the combination of ifosfamide, etoposide, and the uroprotector, mesna (2-mercaptoethane sulphonate), in a phase II trial. The treatment regimen consisted of 12 cycles of therapy administered every 3 weeks. After evaluation of the tumor response to chemotherapy alone, radiation or surgery was used to eradicate residual sites of metastatic disease where possible. At the present time, 77 patients are evaluable for response to the chemotherapy; 43 of the patients have experienced a significant reduction in the tumor size in response to the chemotherapy alone (39 partial responses [PR] and four complete responses [CR]). Sixteen of 17 patients with Ewing's sarcoma, nine of 13 with rhabdomyosarcoma, four of eight with peripheral neuroepithelioma, three of eight with osteosarcoma, and 11 of 31 with other tumors have responded with a PR or CR. The toxicity of the regimen was acceptable. Moderate or severe toxicity evaluated on a per cycle basis included: neutropenia, 97%; thrombocytopenia, 32%; nephrotoxicity, less than 1%; mucositis, 1%; neurologic toxicity, 2%; nausea and vomiting, 13%; hemorrhagic cystitis, less than 1%. Fever was present after 33% of cycles and sepsis following 7%. One patient died due to sepsis and pancytopenia. At the present time, only seven of the 43 patients who responded to the chemotherapy regimen have relapsed, with a median follow-up of 10 weeks after the response. This drug combination is highly active in the treatment of recurrent sarcomas and other tumors in children and young adults.