Results of individual patient dosimetry in peptide receptor radionuclide therapy with 177Lu DOTA-TATE and 177Lu DOTA-NOC.

Abstract

UnlabelledOne of the few treatment options for inoperable neuroendocrine tumors (NET) is peptide receptor radiotherapy with somatostatin analogs. In this study, we compared the dosimetric parameter uptake, half-life (kinetics), and mean absorbed organ and tumor doses of (177)Lu DOTA-NOC and (177)Lu DOTA-TATE.MethodsNinety-five (95) post-therapeutic dosimetric assessments using (177)Lu DOTA-TATE and 8 using (177)Lu DOTA-NOC in 69 patients with neuroendocrine tumors with high somatostatin receptor expression (verified by Ga-68 DOTA-NOC positron emission tomography/computed tomography) were analyzed. Dosimetric calculations were performed according to the Medical Internal Radiation Dose scheme.Results(177)Lu DOTA-NOC showed a significantly (p ConclusionsOur first results demonstrated that the higher in vitro affinity of DOTA-NOC leads to a higher uptake in normal tissues and, therefore, to an increase in the whole-body dose. The high interpatient variability of these results makes an individual patient dosimetry obligatory.