 This phase II trial is studying how well giving cisplatin and irinotecan together with bevacizumab works in treating patients with extensive-stage small cell lung cancer. Drugs used in chemotherapy, such as cisplatin and irinotecan, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Monoclonal antibodies, such as bevacizumab, can block tumor growth in different ways. Some block the ability of tumor cells to grow and spread. Others find tumor cells and help kill them or carry tumor-killing substances to them. Bevacizumab may also stop the growth of small cell lung cancer by blocking blood flow to the tumor. Giving cisplatin and irinotecan together with bevacizumab may kill more tumor cells. 