Purpose

This study is being done to gather information about the safety (any harmful effects) and effectiveness (usefulness) of Pazopanib in the treatment of Gastrointestinal Stroma Tumors (GIST) that cannot be treated by surgery or has spread to other organs. The Food and Drug Administration (FDA) have approved Pazopanib for the treatment of advanced kidney cancer but it is not approved for the treatment of GIST. The investigators hope to learn about the safety and usefulness (effectiveness) of Pazopanib for patients with GIST. Primary Objective: Non-progression rate based on RECIST criteria (CR+PR+SD) Secondary Objectives: * Response per Choi criteria * 6 month progression-free survival * Safety and tolerability