Ribociclib in Treating Patients With Advanced Neuroendocrine Tumors of Foregut Origin

Inclusion Criteria: * Histologically or cytologically confirmed low or intermediate grade, unresectable well differentiated foregut neuroendocrine tumors (thymic, bronchopulmonary, gastric, duodenal and pancreatic); patients with multiple neuroendocrine tumors associated with MEN1 syndrome will be eligible * Patients must have radiographically measurable disease * Pancreatic neuroendocrine patients must have had progression after prior therapy; patients with other foregut neuroendocrine tumors must have had progressive disease over the last 12 months, irrespective of prior therapy; patients with both functional (who may continue somatostatin analogues as required for control of related symptoms) and non-functional tumors are eligible; in patients who have previously received therapy, the number of prior lines of therapy should not be more than 2 lines of systemic therapy not including somatostatin analogues * Written informed consent must be obtained prior to any screening procedures * Patients must have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 1 * A sufficient interval must have elapsed between the last dose of prior anti-cancer therapy (including cytotoxic and biological therapies and major surgery) and enrollment, to allow the effects of prior therapy to have abated: a) cytotoxic or targeted chemotherapy: greater than or equal to the duration of the cycle of the most recent treatment regimen (a minimum of 3 weeks for all regimens, except 6 we…