MR perfusion-weighted imaging in the evaluation of high-grade gliomas after treatment: a systematic review and meta-analysis

Abstract

Background. Distinction between tumor and treatment related changes is crucial for clinical management of patients with high-grade gliomas. Our purpose was to evaluate whether dynamic susceptibility contrast-enhanced (DSC) and dynamic contrast enhanced (DCE) perfusion-weighted imaging (PWI) metrics can effectively differentiate between recurrent tumor and posttreatment changes within the enhancing signal abnormality on conventional MRI. Methods. A comprehensive literature search was performed for studies evaluating PWI-based differentiation of recurrent tumor and posttreatment changes in patients with high-grade gliomas (World Health Organization grades III and IV). Only studies published in the "temozolomide era" beginning in 2005 were included. Summary estimates of diagnostic accuracy were obtained by using a random-effects model. Results. Of 1581 abstracts screened, 28 articles were included. The pooled sensitivities and specificities of each study's best performing parameter were 90% and 88% (95% CI: 0.85-0.94; 0.83-0.92) and 89% and 85% (95% CI: 0.78-0.96; 0.77-0.91) for DSC and DCE, respectively. The pooled sensitivities and specificities for detecting tumor recurrence using the 2 most commonly evaluated parameters, mean relative cerebral blood volume (rCBV) (threshold range, 0.9-2.15) and maximum rCBV (threshold range, 1.49-3.1), were 88% and 88% (95% CI: 0.81-0.94; 0.78-0.95) and , respectively. Conclusions. PWI-derived thresholds separating viable tumor from treatment changes demonstrate relatively good accuracy in individual studies. However, because of significant variability in optimal reported thresholds and other limitations in the existing body of literature, further investigation and standardization is needed before implementing any particular quantitative PWI strategy across institutions.

Perfusion MRI in treatment evaluation of glioblastomas: Clinical relevance of current and future techniques

“…) than treatment effects (Fig. ) . rCBV is high in tumor, as it is reflective of the tumor hyperperfusion volume.…”

Conventional and advanced magnetic resonance imaging in patients with high-grade glioma

“…However, in a large meta-analysis of data from 28 articles published since 2005, the pooled sensitivity and specificity of DSC was 90% and 88%, respectively, for detecting true tumor recurrence in the setting of possible pseudoprogression. 37 Thus the totality of the evidence indicates that DSCis fairly accurate in identifying true tumor progression. Achieving even greater accuracy may require combining DSC data with other advanced imaging modalities such as DTI, 38 ASL, 39 and MRS. 40, 41 This is not guaranteed, however; a recent meta-analysis of 9 studies found that monoparametric and multiparametric MRI performed equally in a clinical context.…”

Prospective comparative diagnostic accuracy evaluation of dynamic contrast‐enhanced (DCE) vs. dynamic susceptibility contrast (DSC) MR perfusion in differentiating tumor recurrence from radiation necrosis in treated high‐grade gliomas

“…CURRENTLY, high‐grade glioma (HGG) treatment consists of combination of surgery, radiation, and chemotherapy (ie, temozolomide). This triple therapy commonly leads to treatment‐related imaging changes in the form of contrast enhancing lesions that closely mimic glioma recurrence on conventional magnetic resonance imaging (MRI) . This imaging dilemma is not uncommon; a recent meta‐analysis revealed that 36% of patients with enhancing lesion on posttreatment MR have treatment‐related changes, while true progression occurred only in 60% of patients .…”

“…This imaging dilemma is not uncommon; a recent meta‐analysis revealed that 36% of patients with enhancing lesion on posttreatment MR have treatment‐related changes, while true progression occurred only in 60% of patients . Compared with conventional MRI, MR perfusion techniques provide information about physiologic parameters of these lesions through its ability to indirectly evaluate tumor neovascularity …”

“…The complexity of image acquisition and the lack of widely available easy‐to‐use postprocessing software are some of the challenges in the routine application of DCE MR. On the other hand, DSC MR suffers from sensitivity to susceptibility artifacts and effects of contrast leakage; however, it remains the most widely used contrast‐enhanced MR perfusion method . Multiple prior studies have shown the usefulness of DSC and DCE in the assessment of treated HGG, but fewer studies compared these two MR perfusion techniques …”