A pilot study of rapidly alternating epirubicin/dacarbazine and ifosfamide as first-line therapy for metastatic soft-tissue sarcoma in adults.

Currently, anthracyclines and ifosfamide are the most effective drugs for the treatment of disseminated soft-tissue sarcoma. We designed a treatment protocol of rapidly alternating epirubicin/dacarbazine and ifosfamide for previously untreated soft-tissue sarcoma, whereby 100 mg/m2 epirubicin was given on day 1, 500 mg/m2 dacarbazine was given on days 1 and 2, and 6,000 mg/m2 ifosfamide given via 24-h infusion was begun on day 15. The entire treatment cycle was scheduled to begin again on day 28 if the leukocyte count had reached 3.0 x 10(9)/l. From June 1988 to May 1991, a total of 28 patients were enrolled in the study. Eight patients (31%) achieved a partial response to therapy. The median duration of partial response was 8.5 months, and the median time to progression for all patients was 5 months. Myelosuppression was dose-limiting (leukocyte nadir, 1.7 x 10(9)/l; platelet nadir, 70 x 10(9)/l). Prolonged myelosuppression forced frequent therapy delays; therefore, only 74% of the planned doses could be given. The nonhematologic toxicity was tolerable. This rapidly alternating treatment protocol was determined to offer no therapeutic advantage over anthracycline therapy either alone or in combination with dacarbazine in terms of response rate or time to disease progression. The inclusion of hematopoietic growth factors, however, might ameliorate the dose-limiting myelosuppression and permit the administration of higher doses.