Since dose intensity of doxorubicin is correlated with the clinical response of 
patients with soft tissue sarcomas and since doxorubicin dose intensity may be 
compromised in combination chemotherapy, we evaluated the use of recombinant 
granulocytemacrophage colony-stimulating factor (rGM-CSF) to ameliorate 
myelosuppression and allow doxorubicin dose escalation in a phase I trial 
utilizing the MAID combination [Mesna 2.5 g/m2/day x 4 days, Adriamycin 
(doxorubicin) 15 mg/m2/day x 4 days, ifosfamide 2.0 g/m2/day x 3 days, 
dacarbazine 250 mg/m2/day x 4 days; to be repeated every 21 days]. Thirteen 
patients were treated. The doxorubicin dose for the first 6 patients was at the 
standard dose of 15 mg/m2/day x 4 days (level 1), while the doxorubicin dose for 
the next 7 patients was escalated by 25% to 18.75 mg/m2/day x 4 days (level 2). 
rGM-CSF was given at 5 micrograms/kg/day, days 5-14. All patients experienced 
moderate to severe myelosuppression, with all patients at dose level 2 requiring 
doxorubicin dose reduction to dose level 1 or lower by their third course of 
treatment. rGM-CSF failed to allow sustained escalation of the doxorubicin dose 
in the MAID regimen.