Cabozantinib in Advanced Pancreatic Neuroendocrine and Carcinoid Tumors

Subjects will take cabozantinib orally, once per day, in cycles of 28 days. During each cycle subjects will have the following procedures: * Physical examination, including measurement of weight and vital signs * Questions regarding any side effects * Blood sample (about 1 tablespoon) for routine laboratory tests of blood cell counts, blood chemistries, organ function and blood clotting * Blood sample (about 4 tablespoons) for research test to measure biomarkers to assess the response to study drug * Urine sample for routine urine tests to monitor health On Day 15 (beginning of week 3) during the first 3 cycles: * Physical examination, including measurement of weight and vital signs * Questions regarding any side effects * Blood sample (about 1 tablespoon) for routine laboratory tests of blood cell counts, blood chemistries, organ function and blood clotting * Blood sample (about 4 tablespoons) for research test to measure biomarkers to assess the response to study drug Subjects will receive a CT scan or MRI every two cycles (every two months) to evaluate disease.