Dynamic susceptibility contrast perfusion imaging in biopsy-proved adult medulloblastoma.
OBJECTIVE
Medulloblastoma (MB) is a high-grade rare brain tumor in adults, with heterogeneous imaging features and variable enhancing patterns. Diffusion and spectroscopy multimodal imaging have already been described in adult MB, yet perfusion has not been explored. This study aimed to evaluate vascularity in adult classic and desmoplastic MB, using perfusion-weighted dynamic susceptibility contrast (DSC) MRI and histopathology.


METHODS
Six histologically proved MB patients were classified as classic (n=3) and desmoplastic (n=3). DSC perfusion MRI was performed in three centers and retrospectively evaluated. Postprocessing included automatic arterial input function, motion and contrast leakage correction. Region of interest (ROI) delineation was performed on three perfusion slices to obtain a total of three cerebral blood volume ratios (rCBV) that were averaged to serve as the main rCBV. Permeability was evaluated on K2 maps.


RESULTS
Low rCBVs were observed in all cases (mean rCBV=1.19±0.39). rCBV values were lower than 2 for classic MB and lower than 1 for desmoplastic MB. All cases showed an increase of permeability on K2 maps.


CONCLUSIONS
Our preliminary results suggest that MB exhibits rCBV values close to 1 and increased permeability on DSC perfusion imaging, especially in desmoplastic cases, which could be explained by fibrous matrix. This type of perfusion pattern contrasts with those given by other enhancing subtentorial tumors such as metastasis, high-grade gliomas or hemangioblastomas.
Service de Radiologie, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Chemin du Grand-Revoyet, 69495 Pierre-Bénite, France.
Marianne
M
Theillac
Centre de Pathologie et de Neuropathologie, Groupement Hospitalier Est, Hospices Civils de Lyon, Bron, France.
David
D
Meyronet
Service de Neuroradiologie, Fondation Ophtalmologique A de Rothschild, Paris, France.
Julien
J
Savatovsky
CREATIS, CNRS UMR 5220 & Inserm U1044, Université Claude Bernard Lyon 1, Villeurbanne, France.
Nikolaos
N
Makris
CREATIS, CNRS UMR 5220 & Inserm U1044, Université Claude Bernard Lyon 1, Villeurbanne, France.
Salem
S
Hannoun
Clinique Universitaire de Neuroradiologie et Imagerie, CHU de Grenoble, Grenoble, France.
Sylvie
S
Grand
Service de Radiologie, Centre Hospitalier Lyon-Sud, Hospices Civils de Lyon, Chemin du Grand-Revoyet, 69495 Pierre-Bénite, France; CREATIS, CNRS UMR 5220 & Inserm U1044, Université Claude Bernard Lyon 1, Villeurbanne, France. Electronic address: francois.cotton@chu-lyon.fr.
François
F
Cotton
D000328:Adult; D000368:Aged; D001706:Biopsy; D003287:Contrast Media; D005260:Female; D006801:Humans; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008297:Male; D008527:Medulloblastoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D012189:Retrospective Studies; D055815:Young Adult
D003287:Contrast Media
Adult; Desmoplastic; Medulloblastoma; Perfusion magnetic resonance imaging