Detection of local microvascular proliferation in IDH wild-type Glioblastoma using relative Cerebral Blood Volume

BackgroundThe microvascular proliferation (MVP) and the microvessel area (MVA) are known as diagnostic and prognostic biomarkers for glioblastoma; nevertheless, its measurement is costly, labor-intense, and invasive. MRI perfusion biomarkers such as such as relative cerebral blood volume (rCBV) may be a feasible alternative to predict MVP and estimate MVA.PurposeThis study aims to evaluate the detection capacity of MRI markers such as rCBV to detect local microvascular proliferation in IDH wild-type glioblastoma. In addition, we aim to analyze the association between rCBV values and the microvessel area in different regions of the tumor.Study typeRetrospective study.Population and subjectsData from 71 tissue blocks belonging to 17 IDH wild-type glioblastoma patients were compiled from the Ivy GAP database.Field Strength/Sequence1.5T or 3.0T. Pregadolinium and postgadolinium-based contrast agent-enhanced T1-weighted MRI, T2- and FLAIR T2-weighted, and dynamic susceptibility contrast (DSC) T2* perfusion.AssessmentWe analyzed preoperative MRIs to establish the association between the maximum and mean relative cerebral blood volume (rCBVmax and rCBVmean) with the presence/absence of microvascular proliferation and with the microvessel area for each tumor block.Statistical testsSpearman’s correlation and Mann-Whitney test.ResultsSignificant positive correlations were found between rCBV and MVA in the analyzed tumor blocks (pData conclusionThe rCBV is shown as significantly different in those tissue blocks with microvascular proliferation from those blocks without it, and it is significantly correlated with microvessels area. This method allows a local detection and definition of MVP and MVA in different regions of the glioblastoma since the first diagnostic stage and in a non-invasive way.