Hydration approximately 50-200cc/hour in adults should begin 6 hours before cyclophosphamide and continue until 24 hours after the last cyclophosphamide dose. Hydration rates need to be individually adjusted by daily weights to maintain dry weight count. BID weights will be obtained. Warning: Participants with renal insufficiency are prone to volume overload. Early institution of ultra filtration or dialysis is recommended. Three-way bladder irrigation may be needed for those participants who cannot tolerate fluid hydration during cyclophosphamide administration and for 24 hours after the last dose of cyclophosphamide. In patients on hemodialysis, cyclophosphamide will be given in the evening and hemodialysis will be performed in the morning daily until the last dose of cyclophosphamide is administered. Close coordination with nephrology service is required.