Radim Jancalek
St. Anne’s University, Czech Republic
Title: Developing role of advanced MRI techniques for diagnosis of glioblastoma relapse after complex oncology treatment
Biography
Biography: Radim Jancalek
Abstract
Glioblastoma (GBM) is the most common primary brain tumor of adults. Despite a multidisciplinary approach, GBM frequently recurs as a new gadolinium-enhanced MRI lesion at or near the site of the original tumor; thus, at the site of high-dose target volume for radiotherapy. An early differentiation between GBM relapse and changes in connection with oncology treatment (pseudoprogression) is still problematic by common imaging techniques. The project goal was to verify whether the combination of apparent diffusion coefficient (ADC) and MR spectroscopy increases specificity of a structural MRI for early differentiation between HGG relapse and pseudoprogression. Patients (n=24) with GBM and structural progression on MRI after neurosurgical resection and chemo-radiotherapy underwent DWI (ADC map) and 1H MR spectroscopy focused on N-acetylaspartate (NAA), choline (Cho), creatine (Cr), lactate (Lac), and lipids (Lip). The etiology of a lesion was established by a subsequent MRI or biopsy and correlated with results of the MR techniques. Compared to pseudoprogression, HGG relapse was characterized by a significantly lower ADC value, lower NAA concentration, and appearance of Lac+Lip spectra. We found very high sensitivity and specificity of ADC value (≤1300x10-6 mm2/s) and Cho/NAA ratio (≥1.4) to designate the MRI lesion with gadolinium uptake as GBM relapse. ADC value and MRS (mainly Cho/NAA ratio) have ability for the early non-invasive differentiation of GBM relapse from pseudoprogression after oncology treatment.