- Serum creatinine ≤ 1.5 mg/dL or estimated GFR (by Cockcroft-Gault) ≥50mL/min or 12 or 24 hour urine creatinine clearance ≥ 50 mL/min, unless renal insufficiency is due to tumoral ureteral obstruction in which case eligibility will be determined by national the principal investigator (or national co-PI or MSKCC co-PI if the national PI is unavailable) with notification of the MSKCC IRB.