Cellular dosimetry of [Lu]Lu-DOTA-[Tyr]octreotate radionuclide therapy: the impact of modeling assumptions on the correlation with in vitro cytotoxicity.

Background: Survival and linear-quadratic model fitting parameters implemented in treatment planning for targeted radionuclide therapy depend on accurate cellular dosimetry. Therefore, we have built a refined cellular dosimetry model for [Lu]Lu-DOTA-[Tyr]octreotate (Lu-DOTATATE) in vitro experiments, accounting for specific cell morphologies and sub-cellular radioactivity distributions.

Methods: Time activity curves were measured and modeled for medium, membrane-bound, and internalized activity fractions over 6 days.