Safety and Efficacy Study of In-111 Pentetreotide to Treat Neuroendocrine Tumors

Inclusion Criteria: * Patients must have received first line standard chemotherapy and/or radiation therapy for neuroendocrine malignancy in the past and failed the therapy. * Patients must have evidence of residual multifocal active tumor. * All patients must sign an informed consent indicating the awareness of the investigational nature of the studies involved. * All patients must have a Karnofsky performance status of at least 60. * Patients must be greater than 18 years of age. * Patients must have measurable and/or followable disease based on either clinical or radiologic exam. * Sensitivity to Indium-111 pentetreotide or any of its components is an absolute contraindication to participation in this trial. * An absolute contraindication is pregnancy as evidenced by the clinical condition, a positive pregnancy test (Beta type Human chorionic gonadotropin (β-HCG) or pelvic ultrasound). * If patients have received prior radionuclide therapy of the same product, there must be documented response to that therapy and/or residual active stable disease. Exclusion Criteria: * Karnofsky performance status of 50 or less. * Patients who are unable to give informed consent. * Patients under 18 years of age. There will be no upper age discrimination. * Patients who are pregnant or those potentially pregnant subjects not willing to practice effective contraceptive techniques during the study period. * Patients with renal insufficiency as defined by a calculated creatinine clearance (based on age, weight and serum creatinine) of 39.9 ml/min or less.