This is a study to determine what dose is acceptably safe for further testing.~In this study, participants are asked to:~undergo SPECT/CT imaging with Lead-203 Pentixather (a radiotracer) to ensure the tumor lesions have the needed receptors~undergo serial blood sampling for during and after the SPECT/CT scan for radiation and dosimetry calculations (to determine how much of the Lead-212 Pentixather to administer)~receive up to 2 infusions of arginine & lysine as a kidney protectant~receive up to 2 infusions of Lead-212 Pentixather, 6 weeks between each infusion~undergo imaging at 3 months post treatment to determine disease response
This is a first-in-human clinical trial evaluating the safety of an alpha-radiation treatment (Lead-212 labelled Pentixather) in patients who have been diagnosed with, and previously treated, for atypical carcinoid lesions of the lung.