Whole-Body [18F]-FDG-PET/MRI for Oncology: A Consensus Recommendation

Abstract

Combined PET/MR imaging (PET/MRI) was proposed for patient management in 2006 with first commercial versions of integrated whole-body systems becoming available as of 2010. PET/MRI followed the prior evolution of hybrid imaging as attested by the successful adoption of combined PET/CT and SPECT/CT since the early 2000 s. Today, around 150 whole-body PET/MRI systems have become operational worldwide. One of the main application fields of PET/MRI is oncologic imaging. Despite the increasing use of PET/MRI, little governance regarding standardized PET/MRI protocols has been provided to date. Standardization and harmonization of imaging protocols is, however, mandatory for efficient on-site patient management and multi-center studies. This document summarizes consensus recommendations on key aspects of patient referral and preparation, PET/MRI workflow and imaging protocols, as well as reporting strategies for whole-body [18F]-FDG-PET/MRI. These recommendations were created by early adopters and key experts in the field of PET, MRI and PET/MRI. This document is intended to provide guidance for the harmonization and standardization of PET/ MRI today and to support wider clinical adoption of this imaging modality for the benefit of patients. Citation Format: Umutlu L, Beyer T, Grueneisen JS et al. Whole-Body [18F]-FDG-PET/MRI for Oncology: A Consensus Recommendation. Nuklearmedizin 2019, 58: 1–9

Adapting Imaging Protocols for PET-CT and PET-MRI for Immunotherapy Monitoring

“…( Figure 1 ). Already in the advent of PET-MRI, the optimization of scan protocols in accordance to specific patient groups (i.e., children) and disease cohorts (i.e., different tumor entities) has been discussed [ 13 , 14 , 15 , 16 ]. Evidently, considering—the still rather seldom performed—scans with PET radiopharmaceuticals labeled with tracers of longer half-lives, such as Zirconium-89 ( 89 Zr; half-life 3.3 days), well matched to the circulation half-lives of antibodies and thus, potentially suitable for immunotherapy monitoring, the scan duration of PET might exceed the time necessary for the MRI sequences [ 17 , 18 ].…”

“…This problem may be solved with the application of modified, faster PET-MRI acquisition protocols. These workflows include, for example, an initial whole-body PET-CT (optimally with new generation scanners offering faster whole-body coverage) followed by fast whole-body PET-MRI acquisitions, which can be completed within less than 20 and 30 min, respectively, within one single radiotracer injection [ 15 , 16 ]. Another algorithm involves dedicated local PET-MRI imaging of defined body regions (typically the main tumor region and the brain, only).…”

Konsensusempfehlung zur strukturierten Befunderstellung onkologischer PET-Hybridbildgebung

“…Zu Fragen der technischen Durchführung existieren sowohl für die PET/CT als auch die PET/MRT Leitlinien bzw. interdisziplinäre Konsensusempfehlungen nationaler und internationaler Fachgesellschaften, wodurch eine klinische Standardisierung und Minimalanforderungen an die Untersuchungsqualität erreicht werden [2][3][4][5][6].…”

Clinically Valuable Quality Control for PET/MRI Systems: Consensus Recommendation From the HYBRID Consortium

“…For PET/MRI, one report exists describing the implementation of a simultaneous hybrid PET/MRI system in an integrated research and clinical setting [19]. Further, two guidelines for oncological whole-body [ 18 F]-FDG-PET/MRI [20,21] have been published. However, there is currently no recommendation dedicated to QC procedures for PET/MRI systems.…”