This is an exploratory biomarker study. Patients with metastatic colorectal cancer will receive regorafenib, which is FDA approved in this setting, on day 1-21 of every consecutive 28 day cycle. Patie
*Log-rank test for 5-year survival rates.†Cutoff point for hospital 65 cases for female breast cancer; 61 cases for colorectal cancer; 62 cases for lung cancer; 41 cases for prostate cancer; and 78 ca