Inclusion Criteria:

- Histologic or cytologic documentation of primary non-small cell lung cancer

- Stage IIIB or IV disease patients who are not candidates for combined modality
therapy (chemoradiotherapy)

- No evidence of symptomatic or untreated brain metastases, spinal cord compression, or
carcinomatous meningitis; patients with central nervous system (CNS) metastases must
be asymptomatic, must have received definitive therapy (>= 6 weeks since resection or
>= 2 weeks since radiotherapy) for brain metastases, and be off steroids or on a
stable dose for 2 weeks prior to registration

- No cavitary lesions

- Patients must have received one chemotherapy regimen for stage IIIB or IV NSCLC; the
regimen must include four cycles of platinum-based doublet chemotherapy with or
without bevacizumab (bevacizumab may not be given beyond the fourth cycle of
chemotherapy); patients must have achieved a complete response, partial response, or
stable disease to first-line chemotherapy and have no evidence of disease
progression; patients will be registered 3-5 weeks following day 1 of cycle 4 of
prior therapy

- No prior adjuvant chemotherapy for stage I-III resected NSCLC or combined modality
therapy for stage III NSCLC

- No other primary therapy (including experimental therapy) for NSCLC; palliative
radiation therapy must have been completed at least one week before planned start of
protocol therapy

- Patients must have measurable or non-measurable disease

- Measurable disease: lesions that can be accurately measured in at least one
dimension (longest diameter to be recorded) as >= 2 cm with conventional
techniques or as >= 1 cm with spiral CT scan

- Non-measurable disease: all other lesions, including small lesions (longest
diameter < 20 mm with conventional techniques or < 10 mm with spiral computed
tomography [CT] scan) and truly non-measurable lesions; lesions that are
considered non-measurable include the following:

- Bone lesions

- Leptomeningeal disease

- Ascites

- Pleural/pericardial effusion

- Lymphangitis cutis/pulmonis

- Abdominal masses that are not confirmed and followed by imaging techniques

- Cystic lesions

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

- Non-pregnant and non-nursing

- No ongoing cardiac dysrhythmias, atrial fibrillation, or history of corrected QT
(QTc) interval >= 500 msec (within 2 years prior to registration); the use of agents
with proarrhythmic potential (e.g., quinidine, procainamide, disopyramide, sotalol,
probucol, haloperidol, risperidone, indapamide, flecainide) is not recommended while
on protocol therapy

- Patients with class I New York Heart Association (NYHA) heart failure are eligible;
patients with a history of class II NYHA heart failure are eligible, provided they
meet at least one of the following criteria:

- Patients with a history of class II heart failure who are asymptomatic on
treatment

- Patients with prior anthracycline exposure

- Patients who have received central thoracic radiation that included the heart in
the radiotherapy port

- Patients with a history of class III or IV NYHA heart failure within 12 months prior
to registration are not eligible

- No myocardial infarction, severe/unstable angina, coronary/peripheral artery bypass
graft or stenting, cerebrovascular accident or transient ischemic attack within the
last year

- Patients with hypertension that cannot be controlled by medications (> 150/100 mmHg
despite optimal medical therapy) are not eligible

- Patients who require use of therapeutic anticoagulation for thromboembolic disease
are not eligible; Note: low doses of coumadin (up to 2 mg daily) are permitted for
prophylaxis of thrombosis

- No history of venous thrombosis, pulmonary embolism, or hypercoagulopathy syndrome

- No history of pulmonary hemorrhage, bleeding diathesis, or evidence of hemoptysis;
patients with blood-tinged or blood-streaked sputum will be permitted on study if the
hemoptysis amounts to less than 5 ml of blood per episode and less than 10 ml of
blood per 24-hour period in the best estimate of the investigator

- Patients with a history of hypothyroidism are eligible, provided they are currently
euthyroid

- None of the following within 28 days of beginning treatment: abdominal fistula,
gastrointestinal perforation, intra-abdominal abscess, serious or non-healing wound,
ulcer, or bone fracture

- The following inhibitors of cytochrome P450 3A4 (CYP3A4) are prohibited within 7 days
before beginning and during treatment with sunitinib: azole antifungals
(ketoconazole, itraconozole), diltiazem, clarithromycin, erythromycin, verapamil,
delavirdine, and HIV protease inhibitors (indinavir, saquinavir, ritonavir,
atazanavir, nelfinavir); the following inducers of CYP3A4 are prohibited within 12
days before beginning and during treatment with sunitinib: rifampin, rifabutin,
carbamazepine, phenobarbital, phenytoin, St. John's Wort, efavirenz, tipranavir;
other inhibitors and inducers of CYP3A4 may be used if necessary, but their use is
discouraged

- Patients unable to take oral medication are not eligible

- Granulocytes >= 1,500/mcl

- Platelet count >= 100,000/mcl

- Total bilirubin =< 1.5 x upper limit of normal (ULN)

- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT)=< 2.5 x ULN;
patients with liver metastases may have AST and ALT =< 5 x ULN; all other patients
will have AST and ALT =< 2.5 x ULN

- Creatinine =< 1.5 mg/dl