Oxaliplatin With FOLFOX4 in Patients With Normal and Abnormal Renal Function

This trial is a phase II study in patients with advanced gastrointestinal (GI) malignancies who will be assigned to one of 4 cohorts (normal, mild, moderate and several renal dysfunction) based on their baseline measured creatinine clearance then treated with FOLFOX4. Standard bone marrow and liver function inclusion and exclusion criteria must be met prior to study treatment. FOLFOX4 in the study is given every 2 weeks (1 cycle = 2 weeks) for up to 12 cycles unless there are treatment delays to allow for recovery from toxic effects. Dose modifications are included for protocol specified toxicities. After 12 treatment cycles on study, patients who are having a beneficial disease response may continue to have oxaliplatin supplied off study to continue the treatment regimen until disease progression, prohibitive toxicity or death. Oxaliplatin pharmacokinetic studies (plasma and urine) are planned during cycles 1 and 2 on each patient. Creatinine clearance will be assessed every 2 cycles and disease status will be assessed every 3 cycles of treatment during the study.