Background: Patients with hepatic or renal dysfunction are often treated with 5-fluorouracil (5-FU), but there are few data to confirm the safety of this practice.
Patients and methods: Patients with solid tumors were eligible if they were able to fit into one of three organ dysfunction cohorts: I, creatinine >1.5 but < or =3.0 mg/dl and normal bilirubin; II, bilirubin >1.5 but <5.0 mg/dl with normal creatinine; or III, bilirubin > or =5.0 mg/dl with normal creatinine. 5-FU doses were escalated separately within each of the three cohorts. Leucovorin (LV) dosage was fixed at 500 mg/m(2). 5-FU was given as a 24-h infusion at 1000, 1800 or 2600 mg/m(2), and plasma concentrations were measured every 3 h during the first two infusions for each patient.
Results: Sixty-four patients were treated. Toxicities did not appear to be related to organ dysfunction cohort. A weekly dose of of 5-FU 2600 mg/m(2) produced dose-limiting toxicity (DLT) in six of 20 evaluable patients. These DLTs included grade 3 fatigue (n = 3), grade 2 neutropenia precluding weekly dosing (n = 1), grade 3 thrombocytopenia (n = 1) and grade 3 mental status changes (n = 1). There was no relationship between serum bilirubin or serum creatinine and 5-FU clearance.
Conclusions: Patients with elevated bilirubin may be safely started on a weekly regimen of 5-FU 2600 mg/m(2) with leucovorin 500 mg/m(2) as a 24-h continuous infusion.