- Adequate hepatic function with total bilirubin ≤ 1.5mg/dL and ALT or AST ≤ 2x ULN. (Patients with liver metastases may have AST/ALT less than or equal to 5x upper limit of normal). Patients with elevated bilirubin secondary to biliary obstruction that have subsequently been stented may enter the protocol with a bilirubin of < 2.0 as long as the bilirubin is falling.