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...

Purpose: 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.

Patients And Methods: 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.

Results: 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.

Conclusion: 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.