RT Journal Article
SR Electronic
T1 Pediatric-type diffuse low-grade gliomas with MYB alterations: Neuroimaging of the Diffuse astrocytomas, <em>MYB</em> or <em>MYBL1</em>-altered
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP ajnr.A8894
DO 10.3174/ajnr.A8894
A1 Coppola, Fiorenza
A1 Bison, Brigitte
A1 Tietze, Anna
A1 Dangouloff-Ros, Volodia
A1 Lequin, Maarten
A1 Sudhakar, Sniya
A1 Jacques, Thomas S
A1 Palomäki, Maarit
A1 Alves, Cesar AP
A1 Mankad, Kshitij
A1 Driever, Pablo Hernáiz
A1 Horn, Svea
A1 Behrens, Lars
A1 Hargrave, Darren R
A1 Morana, Giovanni
A1 Löbel, Ulrike
YR 2025
UL http://www.ajnr.org/content/early/2025/06/24/ajnr.A8894.abstract
AB BACKGROUND AND PURPOSE: Diffuse astrocytoma, MYB or MYBL1-altered is a new tumor type in the family of Pediatric-type diffuse low-grade gliomas and genetically related to angiocentric glioma. Imaging features of Diffuse astrocytoma, MYB or MYBL1-altered are less well known. During our clinical work, we identified a relatively characteristic imaging pattern in a subset of our patients consisting of a large, diffuse hemispheric tumor with displaced central vessels which we termed the "fireworks sign". Therefore, the purpose of this work was to describe the frequency of this sign and any additional imaging characteristics in a large patient cohort.MATERIALS AND METHODS: This international retrospective study included 40 patients from 7 countries. We recorded clinical, genetic and standard radiological features focusing on the presence of the "fireworks sign" but also the presence or absence of a mismatch between T2WI and FLAIR and a FLAIR rim which have both been reported in these patients.RESULTS: Most tumors were unilateral and located in the cerebral hemispheres (most frequently in parietal, temporal and frontal lobes), hypointense on T1WI and hyperintense on T2WI. No tumor showed diffusion restriction. The “fireworks sign” was present in 16 patients. Other features included: T2/FLAIR mismatch (24 cases), FLAIR rim (18 cases), necrosis (5 cases) and enhancement (5 cases). Tumor volume was significantly associated with the “fireworks sign” (p=0.01) and T2/FLAIR mismatch (p=0.005).CONCLUSIONS: Imaging features of Diffuse astrocytoma, MYB1 or MYBL1-altered in children are variable and the “fireworks sign” was identified in a subset of patients only. It was usually present in patients with large hemispheric tumors but also observed in brainstem lesions. Diffusion restriction was consistently absent and enhancement infrequent. A T2/FLAIR mismatch was seen in more than 50% of patients.ABBREVIATIONS: WHO = World Health Organization; DA-MYB = Diffuse astrocytoma, MYB or MYBL1-altered