Inclusion Criteria:

- adult patients, >=18 years of age;

- well-differentiated gastrointestinal tract endocrine tumors, or duodeno-pancreatic
endocrine tumors;

- no previous anti-cancer therapy, other than surgery;

- progressive metastatic disease;

- >=1 measurable lesion.

Exclusion Criteria:

- abnormal cardiac function, with history of ischemic heart disease in past 6 months
and/or abnormal 12 lead ECG;

- patients with known bleeding disorders;

- unstable systemic disease;

- chronic daily treatment with high-dose aspirin, NSAIDs or corticosteroids;

- previous history of malignancy (other than successfully treated basal and squamous
cell cancer of the skin, and/or in situ cancer of the cervix).