RecruitingPhase 1Device studyUsing Novel Imaging to More Safely Treat Neuroendocrine TumorsThe goal of this research is to determine if DetectnetTM PET/CT can be used to make Lutathera therapy safer for patients with neuroendocrine cancer. Participants will: * Complete two phases involving 6 visits * Undergo additional research PET/CT, and possibly SPECT/CT scans