Resveratrol has been shown to activate a protein called Notch-1. Signaling of Notch-1 has been shown to prevent tumor cell growth. Resveratrol has also been shown to prevent growth of tumors in mice. The purpose of this study is to examine the effects of resveratrol and Notch-1 on neuroendocrine tumor tissue and to examine how people with neuroendocrine tumors who take resveratrol for up to three months tolerate the product.

Patients will be treated with a dose of 5 gm/day of resveratrol orally, in two divided doses of 2.5 gm each without a break in therapy for a total of three cycles. All patients who receive at least one dose of resveratrol will be evaluated for toxicity and tolerability. Toxicities will be assessed every 28 days while the study drug is being taken by the patient. Pill bottles will be reviewed at this visit as well to ensure compliance with the study medication. Toxicities will be graded according to the NCI Common Toxicity Criteria. Blood will be drawn for a complete blood count and comprehensive metabolic panel. In addition, one vial of serum will be stored at the time of each toxicity assessment for later analysis of resveratrol levels. This level must be drawn one hour after the morning dose and the participants will be instructed to alter the time of the morning dose so as to allow proper timing with the scheduled blood draw.

During the third cycle of treatment, a post-treatment biopsy will be obtained for study related purposes and will be processed only for research related purposes.

Inclusion Criteria:

1. ECOG performance status of 0-2
2. Age >18 years old
3. Women who are not postmenopausal must have a negative enrollment blood test and agree to use an effective mode of contraception while taking the study medication
4. Greater than four weeks must have elapsed since any previous therapy was administered for the neuroendocrine tumor, including surgery, radiation, chemotherapy or local liver therapy.
5. Octreotide use is allowed but must be initiated at least four weeks prior to enrollment and to the pre-treatment biopsy
6. Able to give informed consent and willing to undergo the post-treatment research biopsy
7. Must be able to take oral medications and be without GI tract obstructive symptoms
8. Subjects with another malignancy for which they are either undergoing treatment with chemotherapy or radiation, or with a malignancy for which such treatments have been recommended, would be excluded or withdrawn from the study.
9. Must agree to abstain from excessive alcohol, as defined by greater than the equivalent of three glasses of wine per day or one six pack of beer per day

Exclusion Criteria:

1. The principal investigator will review each subject's current medications prior to enrollment of the study to ensure that the administration of Resveratrol will not affect their current medications.