Radiotherapy Target Volume Definition in Newly Diagnosed High-Grade Glioma Using 18F-FET PET Imaging and Multiparametric MRI: An Inter Observer Agreement Study

• Published in: Tomography (Ann Arbor) 2022-08, Vol.8 (4), p.2030-2041
• Main Authors: Dissaux, Brieg, Mazouz Fatmi, Doria, Ognard, Julien, Allard, Bastien, Keromnes, Nathalie, Latreche, Amina, Lepeuve, Amandine, Schick, Ulrike, Bourbonne, Vincent, Ben Salem, Douraied, Dissaux, Gurvan, Querellou, Solène
• Format: Article
• Language: English
• Subjects: 18-F-FET-PET/CT; Brain Neoplasms - diagnostic imaging; Brain Neoplasms - pathology; Brain Neoplasms - radiotherapy; Glioma - diagnostic imaging; Glioma - pathology; Glioma - radiotherapy; Gliomas; high-grade glioma; Humans; inter-observer agreement study; Magnetic resonance imaging; Multiparametric Magnetic Resonance Imaging; multiparametric MRI; Observer Variation; PET imaging; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography - methods; Prospective Studies; Radiotherapy; Tomography, X-Ray Computed; tumor volume delineation; Tyrosine
• ISSN: 2379-139X; 2379-1381; 2379-139X
• DOI: 10.3390/tomography8040170

Background: The aim of this prospective monocentric study was to assess the inter-observer agreement for tumor volume delineations by multiparametric MRI and 18-F-FET-PET/CT in newly diagnosed, untreated high-grade glioma (HGG) patients. Methods: Thirty patients HGG underwent O-(2-[18F]-fluoroethyl)-l-tyrosine(18F-FET) positron emission tomography (PET), and multiparametric MRI with computation of rCBV map and K2 map. Three nuclear physicians and three radiologists with different levels of experience delineated the 18-F-FET-PET/CT and 6 MRI sequences, respectively. Spatial similarity (Dice and Jaccard: DSC and JSC) and overlap (Overlap: OV) coefficients were calculated between the readers for each sequence. Results: DSC, JSC, and OV were high for 18F-FET PET/CT, T1-GD, and T2-FLAIR (>0.67). The Spearman correlation coefficient between readers was ≥0.6 for these sequences. Cross-comparison of similarity and overlap parameters showed significant differences for DSC and JSC between 18F-FET PET/CT and T2-FLAIR and for JSC between 18F-FET PET/CT and T1-GD with higher values for 18F-FET PET/CT. No significant difference was found between T1-GD and T2-FLAIR. rCBV, K2, b1000, and ADC showed correlation coefficients between readers