- Patient must have adequate renal and liver function, defined as: serum creatinine less than or equal to 1.5 times the upper limit of normal; serum bilirubin less than or equal to 1.5 times the upper limit of normal (three times the upper limit of normal for patients with hereditary benign hyperbilirubinaemia); transaminases (ALT, AST) less than or equal to 2.5 times the upper limit of normal in patients without liver metastasis, or less than or equal to 5 times the upper limit of normal in patients with liver metastasis.