This study involves taking a study drug called Lutathera.
The overall goal of this study is to see if Lutathera is safe in adolescent
subjects with either a gastroenteropancreatic neuroendocrine tumor (GEP-NET),
or a pheochromocytoma and/or paraganglioma (PPGL). This study will also look at
the levels of radioactivity after Lutathera administration.