177Lu-DOTATATE Modified Delivery Based on Individualized Dosimetry

In order to be eligible to participate in this study, an individual must meet all of the following criteria. A physical, with vital signs, concomitant medication review, and medical history must be completed within 60 calendar days to confirm appropriateness of Lutathera treatment as well as to foundation for listed criteria. Inclusion Criteria: * Provision of signed and dated informed consent form. * Stated willingness to comply with all study procedures and availability for the duration of the study. * Aged ≥ 18 years at time of consent. * Pathologically confirmed (histology or cytology) malignant neoplasm that is determined to be a well-differentiated neuroendocrine tumor (Ki-67 ≤ 20%) with the primary tumor location known or believed to be gastroenteropancreatic origin (GEP-NET) * Disease measuring ≥ 1.5 cm in diameter on CT or MRI as measured per RECIST that shows uptake \> liver background on sstr2 PET/CT with any FDA approved sstr2 imaging agent. SSTR2 PET/CT must have been obtained within 90 days prior to scheduled C1D1 of Lutathera. * Recommended to receive LUTATHERA® therapy for unresectable and/or metastatic neuroendocrine disease. * Adequate performance status (ECOG of 0 or 1; or Karnofsky performance status of ≥70). * Agrees to contraception during therapy. * Neutrophil count within normal limits within 28 days of treatment day 1. * Platelet count within normal limits within 28 days of treatment day 1. * Ability to take oral medication and be willing to adhere …