Combination Chemotherapy and Bevacizumab in Treating Patients With Advanced Neuroendocrine Tumors

DISEASE CHARACTERISTICS: * Histologically or cytologically confirmed neuroendocrine tumor (NET) * Carcinoid at any site, with or without carcinoid syndrome * Pancreatic islet cell tumor * Prior streptozocin-based therapy not required * Poorly differentiated NET of any primary site (this arm closed to accrual May 2009) * Progression with prior treatment with cisplatin-, or carboplatin-based chemotherapy required (unless contraindicated) * The following tumors are not allowed: * Endocrine organ carcinoma * Adrenal gland malignancies * Thyroid carcinoma of any histology * Pheochromocytoma/paraganglioma * Advanced disease * Disease not amenable to surgery, radiotherapy, or combined modality therapy with curative intent * Radiologically or clinically confirmed progressive disease * At least 25% increase in radiologically or clinically measurable disease * At least 20% increase in the longest diameter (LD) of any previously documented lesion * Increase in the sum of the LD of multiple lesions in aggregate of 20%, OR appearance of new lesions OR deterioration in clinical status * Measurable disease * At least 1 unidimensionally measurable lesion ≥ 20 mm by conventional radiographic techniques OR ≥ 10 mm by spiral CT scan * Ultrasound or positron-emission tomography alone not sufficient * Bone lesions, ascites, peritoneal carcinomatosis, pleural or pericardial effusion, and irradiated lesions are not considered measurable disease * Prima…