Comparing Standard and Personalized Dosimetry-Based PRRT Using Lu-177-DOTATOC for Treating Neuroendocrine Tumors

What this Trial Is About

Researchers are evaluating peptide receptor radionuclide therapy PRRT for patients with neuroendocrine neoplasms NENs who are eligible for this treatment. The study compares standard PRRT, which involves four treatments of 7.4 GBq Lu-177-DOTATOC each, with a dosimetry-based approach where doses are adjusted individually based on kidney function and absorbed kidney dose from prior treatments. The goal is to reach a cumulative kidney dose of 24 Gy while monitoring treatment effects and safety. Participants receive either the standard fixed dose or an individualized dose of Lu-177-DOTATOC over four treatments. Those in the dosimetry arm have their first dose based on kidney function, with subsequent doses adjusted up to a maximum of 20 GBq initially and 25 GBq for later treatments. After each treatment, patients undergo SPECTCT scans to measure kidney radiation absorption, with more frequent and detailed scans in the dosimetry group. Bone marrow dosimetry and blood samples are collected to assess exposure and function, with routine blood tests every two weeks after treatments. Participants are involved in multiple assessments including blood and urine sample collection for kidney fibrosis and biobank storage, validated quality of life questionnaires at each treatment, and imaging studies such as CT scans before and after treatment, as well as Ga-68 DOTATOC PET scans at baseline and follow-up times. The primary outcome measure is progression-free survival 12 months after the last patient last visit. Secondary measures include tumor dose assessment throughout the study. The study includes close monitoring of organ function and quality of life over the treatment and follow-up period.

Dosimetry Based PRRT Versus Standard Dose PRRT With Lu-177-DOTATOC in NEN Patients