The effect of 161Tb-vs 177Lu-DOTA-TATE on the absorbed dose distribution in mouse kidney tissues: small-scale dosimetry at the level of nephron substructures

Preclinical renal dosimetry on nephron level is of interest for investigating nephrotoxicity in radiopharmaceutical therapy (RPT). Depending on the radionuclide decay properties, the non-uniform retention of radioligands in nephron substructures can lead to a heterogeneous absorbed dose distribution in kidney tissues that affects organ response to irradiation. 161Tb is an interesting candidate for RPT due to its higher yield of low energy electrons compared to 177Lu, leading to a potential therapeutic gain caused by more localized irradiation of tumor tissues, but the influence on the absorbed-dose dependent biological effect on normal tissues is unknown. This study investigated and compared the absorbed dose distribution on nephron level of [161Tb]Tb- and [177Lu]Lu-DOTATATE in mice.