This multicenter phase II trial is designed to study the unique combination of chemotherapy (irinotecan./carboplatin) and bevacizumab in the extensive-stage setting. This clinical setting seems ideal for evaluation of the role of bevacizumab in delaying progression and prolonging survival.

Eligible patients will receive 6 courses of irinotecan, carboplatin, and bevacizumab. The interval between chemotherapy courses will be 28 days. If after 6 courses of treatment, patient's response is a CR/PR/SD they will continue on Bevacizumab until tumor progression or up to 6 cycles (6 months) total.

Treatment sequence:

• Irinotecan 60mg/m2 on days 1, 8, and 15
• Carboplatin AUC=4 day 1 only
• Bevacizumab 10 mg/kg days 1 and 15

Inclusion Criteria:

• Histologically confirmed small cell lung cancer,extensive stage disease.
• Measurable or evaluable disease
• No previous chemotherapy
• Able to perform activities of daily living with minimal assistance
• Adequate hematological, live and kidney function
• Provide written informed consent

Exclusion Criteria:

• Limited stage disease
• PEG or G tubes
• Hemoptysis
• Abdominal fistula, perforation, or abscess within the previous 6 months
• Women who are pregnant or lactating
• Proteinuria
• Serious nonhealing wound, ulcer, or bone fracture
• Evidence of bleeding diathesis or coagulopathy
• Uncontrolled or serious cardiovascular disease
• Uncontrolled brain metastasis
• Major surgical procedure, open biopsy, or significant traumatic injury within 28 days; Fine needle aspiration within 7 days
• Patients requiring full-dose anticoagulation must be on a stable dosing schedule prior to enrollment