This is an investigational study. Pazopanib is FDA approved and commercially available for the treatment of advanced kidney cancer and certain types of advanced soft tissue sarcoma such as bone, cartilage, fat, or muscle. Topotecan is FDA approved and commercially available for the treatment of metastatic ovarian cancer that has returned after treatment and for the treatment of small cell lung cancer that has returned after first-line treatment. Topotecan is also FDA approved to treat advanced, recurrent or persistent carcinoma of the cervix in combination with cisplatin. The use of these drugs in combination is investigational. The study doctor can explain how the drugs are designed to work.