 This is an open-label study to provide expanded access to TAS-102 prior to its commercial availability for patients with metastatic colorectal cancer who have been previously treated with, or are not candidates for fluoropyrimidine-, irinotecan-, and oxaliplatin-based chemotherapy, an anti-vascular endothelial growth factor VEGF therapy, and an anti-epidermal growth factor receptor EGFR therapy. 