Temozolomide and Pazopanib Hydrochloride in Treating Patients With Advanced Pancreatic Neuroendocrine Tumors That Cannot Be Removed By Surgery

PRIMARY OBJECTIVES: I. Determine the maximum tolerated dose (MTD) of temozolomide and pazopanib (pazopanib hydrochloride) combination in patients with advanced PNET. (Phase I) II. Determine the overall response rate (ORR). (Phase II) SECONDARY OBJECTIVES: I. Determine safety and toxicity profile of the combination of temozolomide and pazopanib in this population. (Phase I) II. Describe the pharmacokinetics of temozolomide alone and in combination with pazopanib. (Phase I) III. Observe the ORR. (Phase I) IV. Determine progression-free survival (PFS) and overall survival (OS), disease control rate (DCR), and duration of response (DOR). (Phase II) V. Determine the safety and toxicity profile of the combination in a larger cohort of patients. (Phase II) TERTIARY OBJECTIVES: I. Examine the relationship between tumor blood flow, as measured by perfusion functional computed tomography (f CT), and overall response. II. Correlate the expression of tissue methyl-guanine methyl transferase (MGMT) as measured by immunohistochemistry (IHC) with ORR and PFS. OUTLINE: This is a phase I, dose-escalation study followed by a phase II study. Patients receive temozolomide orally (PO) once daily (QD) on days 1-7 and 15-21 and pazopanib hydrochloride PO QD on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 3 months.