* For the treatment of patients with metastatic colorectal cancer: - In combination with 5-fluorouracil and folinic acid in patients without prior chemotherapy for metastatic disease. - As a single agent in patients who have failed an established 5-fluorouracil containing treatment regimen. * For the treatment of patients with small cell lung cancer.* For the treatment of patients with gastric cancer.* Irinotecan in combination with leucovorin, Oxaliplatin and 5-fluorouracil, for the first-line treatment of patients with metastatic pancreatic adenocarcinoma.