Author: NadĂšge Anizan, Jean-NoĂ«l Badel, Thomas Baudier, David Broggio, DĂ©sirĂ©e Deandreis, Ludovic Ferrer, Didier Franck, Camilo Garcia, Jean Gasteuil, Anne-Laure Giraudet, Olivier Humbert, Laetitia Imbert, Malick Koulibaly, StĂ©phanie Lamart, SĂ©bastien Leygnac, Alexandre Pignard, Caroline Rousseau, Guido Rovera, David Sarrut, Paul Schwartz, Nicolas Varmenot đšâđŹ
Affiliation: Institut de CancĂ©rologie de lâOuest, Service de MĂ©decine NuclĂ©aire, Gustave Roussy, Service de Physique MĂ©dicale, Institut BergoniĂ©, Service de Physique MĂ©dicale, CHRU de Nancy Brabois, Service de MĂ©decine NuclĂ©aire, Centre de lutte contre le cancer LĂ©on BĂ©rard, UniversitĂ© de Lyon, Centre Antoine Lacassagne, Service de MĂ©decine NuclĂ©aire, UniversitĂ© Nice CĂŽte dâAzur, Centre Antoine Lacassagne, Service de MĂ©decine NuclĂ©aire, Gustave Roussy, Service de MĂ©decine NuclĂ©aire, Institut de CancĂ©rologie de lâOuest, Service de Physique MĂ©dicale, Service de MĂ©decine NuclĂ©aire, AutoritĂ© de SĂ»retĂ© NuclĂ©aire et de Radioprotection (ASNR), PSE-SANTE/SDOS/LEDI, AutoritĂ© de SĂ»retĂ© NuclĂ©aire et de Radioprotection (ASNR), PSE-SANTE/SDOS, CREATIS CNRS UMR 5220; INSERM U 1044; UniversitĂ© de Lyon; INSAâLyon, CREATIS CNRS UMR 5220; INSERM U 1044; UniversitĂ© de Lyon; INSAâLyon; Centre de lutte contre le cancer LĂ©on BĂ©rard, Institut BergoniĂ©, Service de MĂ©decine NuclĂ©aire đ
Purpose: The main objective of the Lu-PSMA-Dose study, sponsored by ASNR, is to estimate retrospectively the individual absorbed dose delivered to patients treated with 177Lu-PSMA for metastatic castration-resistant prostate cancer (mCRPC). Secondary objectives are: to develop a dose estimation method easily applicable in clinical practice, to provide knowledge on 177Lu-PSMA treatments by computing absorbed doses to lesions and organs at risk on a representative cohort of patients, to determine associated dose uncertainties using a Bayesian network, to carry out an ancillary study on toxicities and to compare them with calculated absorbed doses.
Methods: To set up a cohort of mCRPC patients and to obtain results as generalizable as possible to various imaging protocols, several clinical partners have been invited to contribute to this observational study. Inclusion criteria are: mCRPC patients treated with 177Lu-PSMA according to standard care, and with post-therapeutic SPECT/CT images. Data collected for each patient include these multi-time point images, baseline and in-treatment 68Ga-PSMA PET/CT images, clinical and biological follow-up data. Calibration images for each camera are also collected. The dosimetry workflow should provide personalized absorbed doses based on patient-specific anatomy and biokinetics of Lu-PSMA, for each lesion and organs at risk, including a realistic model of red bone marrow.
Results: Lu-PSMA-Dose has been approved by our local ethical committee and six French nuclear medicine departments are already involved. PET/CT and SPECT/CT images have been collected for 23 patients treated with 177Lu-PSMA in two clinical centers. A full dosimetry workflow has been developed and applied to the first treatment cycle providing dose results for more than 400 individual lesions.
Conclusion: These primary results indicate that the Lu-PSMA-Dose study will be essential in providing knowledge on treatments with Lu-PSMA and is promising for contributing in a better understanding of lesion response and toxicities to healthy tissues.