Pazopanib Hydrochloride in Treating Patients With Progressive Carcinoid Tumors

Inclusion Criteria: * Low- or intermediate-grade neuroendocrine carcinoma, including the following subtypes: carcinoid tumor, low- to intermediate-grade or well- to moderately-differentiated neuroendocrine carcinoma or tumor, atypical carcinoid tumor; documentation from a primary tumor or metastatic site is sufficient; patients with poorly differentiated neuroendocrine carcinoma, high-grade neuroendocrine carcinoma, adenocarcinoid tumor, or goblet cell carcinoid tumor are not eligible * Locally unresectable or metastatic carcinoid tumors * Patients must have histologic documentation or clinical evidence of a carcinoid tumor of primary site (including foregut, midgut, hindgut or other non-pancreatic site); tumors of unknown primary site are eligible provided the treating physician does not suspect medullary thyroid cancer, pancreatic neuroendocrine tumor, paraganglioma, or pheochromocytoma; unknown primary tumors will be classified as small bowel tumors for the purpose of stratification; functional (associated with a clinical syndrome) or nonfunctional tumors are allowed; target lesions must have shown disease progression if therapy included peptide receptor radiotherapy (PRRT) and PRRT must be completed at least 8 weeks prior to registration * Radiological evidence for progressive disease (measurable or non-measurable) within 12 months prior to registration; patients who have received anti-tumor therapy during the past 12 months (including octreotide analogs) must have had r…