Comparing Capecitabine and Temozolomide in Combination to Lutetium Lu 177 Dotatate in Patients With Advanced Pancreatic Neuroendocrine Tumors

Inclusion Criteria: * Histologic or pathologic documentation: well-differentiated pancreatic neuroendocrine tumor (G1, G2, or well-differentiated G3) confirmed by local histology and/or pathology * Functional or nonfunctional tumors are allowed * Stage: locally unresectable or metastatic disease * Tumor Site: neuroendocrine tumor of pancreatic primary site * Radiologic evaluation: tumor must have shown somatostatin receptor (SSTR) positivity on 68Ga-DOTATATE PET or other SSTR-PET scan in the 12 months prior to registration; however, documentation of SSTR positivity in the 6 months prior to registration is preferred. SSTR positivity is defined as uptake greater than background liver in all measurable lesions * Patients are eligible if they meet one of the following criteria: * Previously untreated patients with grade 2 or 3 disease AND with symptoms of either disease bulk causing pain, anorexia, early satiety, large effusions/ascites, abdominal pain, abdominal fullness due to hepatomegaly, dyspnea) OR incompletely controlled symptoms of hormone excess despite somatostatin analogue (SSA) and supportive care (including but not limited to: diarrhea, hypercalcemia, hypoglycemia, hyperglycemia, flushing, Cushing's syndrome). Patient may have been started on SSA for up to 2 months for attempted symptom control without disease progression prior to registration * Patients previously treated with SSA only and with disease progression by RECIST in prior 12 months * Patients prev…