Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed low-grade neuroendocrine tumors

- The following tumor types are excluded:

- Small cell lung cancer

- Medullary thyroid cancer

- Paraganglioma

- Pheochromocytoma

- Measurable disease

- Radiographic evidence of disease progression after completion of any prior systemic
therapy, chemoembolization, bland embolization, or observation within the past year,
defined as either of the following:

- Appearance of a new lesion

- At least 20% increase in the longest diameter (LD) of any previously documented
lesion or an increase in the sum of the LDs of multiple lesions in the aggregate of
20%

PATIENT CHARACTERISTICS:

Age

- 18 and over

Performance status

- ECOG 0-2

Life expectancy

- Not specified

Hematopoietic

- Absolute neutrophil count ≥ 1,000/mm^3

- Platelet count ≥ 75,000/mm^3

- Hemoglobin ≥ 8.0 g/dL

Hepatic

- Bilirubin ≤ 2.0 times upper limit of normal (ULN)

- AST ≤ 3 times ULN (5 times ULN if liver metastases are present)

Renal

- Creatinine ≤ 1.5 times ULN

- Meets 1 of the following criteria:

- Urine protein negative by dipstick

- Urine protein:creatinine ratio < 1.0

- Urine protein < 1 g by 24-hour urine collection

Gastrointestinal

- Must be able to swallow tablets

- No ulcerative disease

- No uncontrolled nausea, vomiting, or diarrhea

- No bowel obstruction

- No other gastrointestinal tract disease resulting in an inability to take oral
medication

Other

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- Must be able to receive a contrast-enhanced CT scan

- No known history of allergic reaction to vatalanib or its derivatives or octreotide
injections

PRIOR CONCURRENT THERAPY:

Biologic therapy

- Not specified

Chemotherapy

- At least 4 weeks since prior chemotherapy

- No more than 1 prior systemic chemotherapy regimen

- Chemoembolization is not considered systemic chemotherapy

- No concurrent chemotherapy

Endocrine therapy

- Not specified

Radiotherapy

- At least 3 weeks since prior radiotherapy

- No concurrent radiotherapy

Surgery

- At least 4 weeks since prior major surgery

Other

- At least 4 weeks since other prior systemic therapy

- At least 4 weeks since prior local liver therapy

- No prior anti-vascular endothelial growth factor agents

- No concurrent grapefruit or grapefruit juice

- No concurrent therapeutic warfarin or similar oral anticoagulants that are
metabolized by the cytochrome P450 system

- Concurrent heparin allowed