BACKGROUND Peptide receptor radionuclide therapy (PRRT) with 177Lu-[DOTA0,Tyr3]octreotate (177Lu-octreotate) is generally performed using a fixed activity of 7.4 GBq (200 mCi) per course bound to 180 to 300 μg of the peptide. While this single activity may lead to suboptimal radiation doses in neuroendocrine tumors (NET) with advanced or bulky disease, dose escalation has been withheld due to c...