1. To identify the ideal dose of the combination of CHOP-R with PEG-Filgrastim (Neulasta) using first a fixed dose of Neulasta and an escalating dose of GM-CSF (Leukine) up to 250 mcg. When that dose is reached, if possible, the dose of Neulasta will be increased stepwise. CHOP-R will be delivered every 14 days at a fixed standard dose with dose adjustments of PEG-Filgrastim and GM-CSF upwards and downwards according to nadir or zenith blood counts.