title: Nonenhancing peritumoral hyperintense lesion on diffusion-weighted imaging in glioblastoma: a novel diagnostic and specific prognostic indicator.
abstract: OBJECTIVE Glioblastoma differentials include intracranial tumors, like malignant lymphomas and metastatic brain tumors with indiscernible radiological characteristics. The purpose of this study was to identify a distinct radiological feature for the preoperative differentiation of glioblastoma from its differentials, which include malignant lymphomas and metastatic brain tumors. METHODS Preoperative MR images, including diffusion-weighted imaging (DWI) studies (b = 1000 and 4000 sec/mm2), obtained in patients with newly diagnosed malignant tumor, were analyzed retrospectively after receiving approval from the institutional review board. Sixty-four patients with histologically confirmed glioblastoma, 32 patients with malignant lymphoma, and 46 patients with brain metastases were included. The presence of a nonenhancing peritumoral DWI high lesion (NePDHL, i.e., hyperintense lesion in a nonenhancing peritumoral area on DWI) was confirmed in both DWI sequences. Gray matter lesions were excluded. Lesions were termed "definite" if present within 3 cm of the hyperintense tumor border with a signal intensity ratio ≥ 30% when compared with the contralateral normal white matter in both sequences. Discriminant analysis between the histological diagnosis and the presence of Definite-NePDHL was performed, as well as Kaplan-Meier survival analysis incorporating the existence of Definite-NePDHL. RESULTS In 25% of glioblastoma patients, Definite-NePDHL was present, while it was conspicuously absent in patients with malignant lymphoma and metastatic brain tumors. The specificity and positive predictive value were 100%. In the glioblastoma subset, a higher preoperative Karnofsky Performance Scale score (p = 0.0028), high recursive partitioning analysis class (p = 0.0006), and total surgical removal (p = 0.0012) were associated with better median overall survival. Patients with Definite-NePDHL had significantly early local (p = 0.0467) and distant/dissemination recurrence (p < 0.0001) and poor prognosis (p = 0.0007). CONCLUSIONS The presence of Definite-NePDHL is very specific for glioblastoma and indicates poor prognosis. Definite-NePDHL is a significant indicator of early local and distant/dissemination recurrence in patients with glioblastoma. Studying peritumoral DWI and high-b-value DWI is useful for tumor differentiation.
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Manish
authors.initials: M
authors.lastname: Kolakshyapati
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Rupendra B
authors.initials: RB
authors.lastname: Adhikari
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Vega
authors.initials: V
authors.lastname: Karlowee
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Takayasu
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Ryo
authors.initials: R
authors.lastname: Nosaka
authors.affiliation: 2Pathology.
authors.forename: Vishwa J
authors.initials: VJ
authors.lastname: Amatya
authors.affiliation: 2Pathology.
authors.forename: Yukio
authors.initials: Y
authors.lastname: Takeshima
authors.affiliation: 3Clinical Radiology, and.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Akiyama
authors.affiliation: 4Clinical Oncology and Neuro-oncology Program, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima,Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sugiyama
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Kurisu
authors.affiliation: Departments of1Neurosurgery.
authors.forename: Fumiyuki
authors.initials: F
authors.lastname: Yamasaki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D002648:Child; D003937:Diagnosis, Differential; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015996:Survival Rate; D055815:Young Adult
keywords: ADC = apparent diffusion coefficient; ADCMIN = minimum absolute ADC; BBB = blood-brain barrier; CNWM = contralateral normal white matter; DTI = diffusion tensor imaging; DWI; DWI = diffusion-weighted imaging; IDH-1 = isocitrate dehydrogenase 1; KPS = Karnofsky Performance Scale; NePDHL = nonenhancing peritumoral DWI high lesion; ROI = region of interest; RPA = recursive partitioning analysis; SIR = signal intensity ratio; T1WI = T1-weighted imaging; T2*WI = T2*-weighted imaging; diffusion restriction; glioblastoma; high b-value; oncology; peritumoral region