Inclusion Criteria:

- Low- or intermediate-grade neuroendocrine carcinoma, including the following
subtypes: carcinoid tumor, low- to intermediate-grade or well- to
moderately-differentiated neuroendocrine carcinoma or tumor, atypical carcinoid
tumor; documentation from a primary tumor or metastatic site is sufficient; patients
with poorly differentiated neuroendocrine carcinoma, high-grade neuroendocrine
carcinoma, adenocarcinoid tumor, or goblet cell carcinoid tumor are not eligible

- Locally unresectable or metastatic carcinoid tumors

- Patients must have histologic documentation or clinical evidence of a carcinoid tumor
of primary site (including foregut, midgut, hindgut or other non-pancreatic site);
tumors of unknown primary site are eligible provided the treating physician does not
suspect medullary thyroid cancer, pancreatic neuroendocrine tumor, paraganglioma, or
pheochromocytoma; unknown primary tumors will be classified as small bowel tumors for
the purpose of stratification; functional (associated with a clinical syndrome) or
nonfunctional tumors are allowed; target lesions must have shown disease progression
if therapy included peptide receptor radiotherapy (PRRT) and PRRT must be completed
at least 8 weeks prior to registration

- Radiological evidence for progressive disease (measureable or non-measurable) within
12 months prior to registration; patients who have received anti-tumor therapy during
the past 12 months (including octreotide analogs) must have had radiological
documentation of progression of disease while on or after receiving therapy

- No known endobronchial lesions and/or lesions infiltrating major pulmonary vessels
that increase the risk of pulmonary hemorrhage; patients with lesions infiltrating
major pulmonary vessels (contiguous tumor and vessels) are excluded; however, the
presence of a tumor that is touching, but not infiltrating (abutting) the vessels is
acceptable (computed tomography [CT] with contrast is strongly recommended to
evaluate such lesions); patients with large protruding endobronchial lesions in the
main or lobar brochi are excluded; however, endobronchial lesions in the segmented
bronchi are allowed

- Patients must have measurable disease per RECIST 1.1 by computed tomography (CT) scan
or magnetic resonance imaging (MRI); lesions must be accurately measured in at least
one dimension (longest diameter to be recorded) as >= 1 cm with CT or MRI (or >= 1.5
cm for lymph nodes)

- No prior treatment with an inhibitor of vascular endothelial growth factor (VEGF) or
vascular endothelial growth factor receptor (VEGFR)

- Prior treatment (somatostatin analogs excepted) must be completed at least 4 weeks
prior to registration, and any treatment-related toxicities must have improved to =<
grade 1

- Concurrent use of somatostatin analogs (SSTa) is allowed, provided that the patient
is on a stable dose for at least two months and progressive disease on somatostatin
analog has been documented

- Prior treatment with embolization (including bland embolization, chemoembolization,
and selective internal radiation therapy) or ablative therapies is allowed if
measurable disease remains outside of the treated area or there is documented disease
progression in a treated site; there is no limit on the prior number of procedures;
prior liver-directed or other ablative treatment must be completed at least 8 weeks
prior to registration

- Patients should have completed any major surgery >= 4 weeks prior to registration and
must have completed any minor surgery >= 2 weeks prior to registration; patients must
have fully recovered from the procedure

- The following are examples of procedures considered to be minor: port placement,
laparoscopy, thoracoscopy, bronchoscopy, mediastinoscopy, skin biopsies,
incisional biopsies, imaging-guided biopsy for diagnostic purposes, and dental
extraction procedures

- Insertion of a vascular access device, thoracentesis, paracentesis, and
endoscopic ultrasonographic procedures are not considered to be major or minor
surgeries

- No concurrent condition resulting in immune compromise, including chronic treatment
with corticosteroids or other immunosuppressive agents

- No clinical evidence of central nervous system (CNS) metastases (including
carcinomatous meningitis) at baseline, with the exception of those patients who have
previously-treated CNS metastases (surgery +/- radiotherapy, radiosurgery, or gamma
knife) and who meet both of the following criteria: a) are asymptomatic and b) had no
requirement for steroids or enzyme-inducing anticonvulsants within 6 months prior to
registration

- No history of abdominal fistula, gastrointestinal perforation, or intra-abdominal
abscess within 28 days prior to registration

- No clinically significant gastrointestinal abnormalities that may increase the risk
for gastrointestinal bleeding within 28 days prior to registration including, but not
limited to:

- Active peptic ulcer

- Known endoluminal metastatic lesion(s) with history of bleeding

- Inflammatory bowel disease (e.g. ulcerative colitis, Crohn's disease), or other
gastrointestinal conditions with increased risk of perforation

- No history of serious (i.e., requiring active medical therapy with medication or
medical device under the supervision of a physician) non-healing wound, ulcer,
trauma, or bone fracture within 28 days prior to study entry

- Patients with a history of hypertension must have blood pressure that is adequately
controlled on antihypertensives; (< 140/90 mmHg)

- No symptomatic congestive heart failure (New York Heart Association class II, III, or
IV) within 6 months prior to registration

- No arterial thrombotic events within 6 months of registration, including transient
ischemic attack (TIA), cerebrovascular accident (CVA), peripheral arterial thrombus,
unstable angina or angina requiring surgical or medical intervention in 6 months
prior to registration, or myocardial infarction (MI); patients with clinically
significant peripheral artery disease (i.e., claudication on less than one block) are
ineligible; patients who have experienced a deep venous thrombosis or pulmonary
embolus within 6 months prior to registration must be on stable therapeutic
anticoagulation for at least 6 weeks prior to enrollment of this study

- Patients on therapeutic anticoagulation with low molecular weight heparins,
fondaparinux, or warfarin are eligible, provided that they are on a stable dose of
anticoagulants; patients who are currently receiving antiplatelet therapy of
prasugrel or clopidogrel or antiaggregation agents (e.g., eptifibatide, epoprostenol,
dipyridamole) or low doses of acetylsalicylic acid (up to 100 mg daily) are also
eligible

- No ongoing cardiac dysrhythmias, atrial fibrillation, or prolongation of corrected
QTc interval to > 480 msec

- No evidence of active bleeding, bleeding diathesis, or hemoptysis (>= 1/2 teaspoon of
red blood) within 8 weeks prior to registration

- No currently unstable angina and/or uncontrolled cardiac arrhythmias

- Patients with symptomatic peripheral vascular disease are ineligible

- Ejection fraction on echocardiogram (Echo) or multi gated acquisition scan (MUGA) >
50%

- Women must not be pregnant or nursing; women of child bearing potential must have a
negative serum or urine pregnancy test (minimum sensitivity 25 IU/L or equivalent
units of human chorionic gonadotropin [HCG]) within 72 hours prior to registration;
women of child-bearing potential include any female who has experienced menarche and
who has not undergone surgical sterilization (hysterectomy, bilateral tubal ligation
or bilateral oophorectomy) or is not postmenopausal (defined as amenorrhea >= 12
consecutive months; or women on hormone replacement therapy [HRT] with documented
serum follicle stimulating hormone [FSH] level > 35 mIU/mL)

- Eastern Cooperative Oncology Group (ECOG) performance status 0-1

- Granulocytes >= 1,500/mcL

- Platelets >= 100,000/mcL

- International normalized ratio (INR) =< 1.2 X upper limit of normal ULN; patients
receiving anticoagulant therapy are eligible if their INR is stable and within the
recommended range for the desired level of anticoagulation

- QTc =< 480 msecs

- Thyroid stimulating hormone (TSH) within normal limits (WNL)

- Bilirubin =< 1.5 x ULN

- Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT]) &
alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) =< 2.5
x ULN; concomitant elevations in bilirubin and AST/ALT above 1.0 X ULN are NOT
permitted; also, if liver metastases are present, AST & ALT =< 5 x ULN is allowed

- Serum creatinine =< 1.5 x ULN

- Urine protein to creatinine (UPC) ratio < 1, or, 24-hour urine protein < 1g; if UPC
>= 1, then a 24-hour urine protein must be assessed; patients must have a 24-hour
urine protein value < 1 g to be eligible; use of urine dipstick for renal function
assessment is not acceptable