Pazopanib Hydrochloride in Treating Patients With Advanced Neuroendocrine Cancer

PRIMARY OBJECTIVE: I. To determine the objective response rate (ORR) (complete and partial response) of GW786034 (pazopanib hydrochloride) 800 mg administered orally once daily in patients with advanced low or intermediate grade carcinoid tumors (in carcinoid cohort). II. To determine the objective response rate (ORR) (complete response and partial response) of GW786034 800mg administered orally once daily in patients with advanced low or intermediate grade pancreatic islet cell carcinoma (in islet cell cohort). SECONDARY OBJECTIVES: I. To determine the progression free survival (PFS) duration of GW786034 800mg administered orally once daily in patients with low grade neuroendocrine carcinoma. II. To determine the safety and tolerability of GW786034 800mg administered orally once daily in patients with low grade neuroendocrine carcinoma. III. To explore the effect on tumor blood flow as determined by functional computed tomography (CT) of GW786034 800 mg orally once daily in patients with low grade neuroendocrine carcinoma. IV. To assess the trough level of GW786034 800 mg orally once daily in patients with low grade neuroendocrine carcinoma. OUTLINE: Patients receive pazopanib hydrochloride orally (PO) once daily (QD) on days 1-28. Treatment repeats every 28 days for 12 courses in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed every 90 days for up to 18 months.