Granulocyte-macrophage colony-stimulating factor allows safe escalation of dose-intensity of chemotherapy in metastatic adult soft tissue sarcomas: a study of the European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group.

Abstract

This study was designed to test the feasibility of administering doxorubicin at an optimal dose-intensity (> 70 mg/m2 per 21 days) in combination with ifosfamide under recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) cover in patients with metastatic soft tissue sarcomas. One hundred four eligible patients (of 111 entered) in 16 centers received doxorubicin 75 mg/m2 plus ifosfamide 5 g/m2 every 3 weeks for up to seven cycles. rhGM-CSF (250 micrograms/m2) was administered once or twice daily by subcutaneous injections for up to 14 days between cycles of chemotherapy. Full protocol dose-intensity of chemotherapy was administered to the majority of patients with only 15 of 293 cycles being complicated by febrile episodes that required hospitalization. There were two treatment-related deaths: one from septicemia and one from cardiac failure. The main toxicities attributed to rhGM-CSF were pruritus and rash. A 45% response rate (10% complete remission [CR]) was seen, with a median response duration of 9 months and median survival of 15 months. This high-dose regimen of chemotherapy was feasible under rhGM-CSF cover and produced a higher response rate and median survival than previously seen by the European Organization for Research and Treatment of Cancer (EORTC) Soft Tissue Sarcoma Group. A randomized phase III study is now underway comparing this regimen with conventional-dose doxorubicin/ifosfamide to test the dose-response relationship.