Telomerase reverse transcriptase promoter mutation and histologic grade in IDH wild-type histological lower-grade gliomas: The value of perfusion-weighted image, diffusion-weighted image, and 18F-FDG-PET. Issue 159 (February 2023)

• Record Type: Journal Article
• Authors: Ikeda, Satoshi; Sakata, Akihiko; Fushimi, Yasutaka; Okuchi, Sachi; Arakawa, Yoshiki; Makino, Yasuhide; Mineharu, Yohei; Nakajima, Satoshi; Hinoda, Takuya; Yoshida, Kazumichi; Miyamoto, Susumu; Nakamoto, Yuji
• Is Part Of: European journal of radiology. Issue 159(2023)
• Publication Date: 2023-02
• Subjects: Glioma -- Magnetic resonance imaging -- Positron emission tomography -- Isocitrate dehydrogenase -- Telomerase reverse transcriptase; ADC apparent diffusion coefficient -- DSC-PWI dynamic susceptibility contrast perfusion weighted imaging -- 18F-FDG-PET 18F-fluorodeoxyglucose-positioron emission tomography -- FLAIR fluid-attenuated inversion recovery -- IDH isocitrate dehydrogenase -- IDHwt IDH-wildtype -- LGA lower grade astrocytoma -- nADC normalized apparent diffusion coefficient -- nrCBV normalized relative cerebral blood volume -- rCBV relative cerebral blood volume -- ROI region of interest -- SUV standardized uptake value -- TERTp telomerase reverse transcriptase promoter -- T/N ratio tumor-to-normal ratio -- VOI volume of interest; Medical radiology -- Periodicals; Radiology -- Periodicals; Radiologie médicale -- Périodiques; Medical radiology; Periodicals; 616.075705
• DOI: 10.1016/j.ejrad.2022.110658
• Languages: English
• ISSNs: 0720-048X

Abstract

Highlights: TERT p mutations are important molecular markers that predict the aggressiveness of IDH wild-type lower-grade astrocytoma ( IDH wt LGA). DSC-PWI, DWI and 18 F-FDG-PET are useful in assessing histological grade of IDH wt LGA. Neither conventional MRI characteristics nor semi-quantitative biomarkers derived from PWI, DWI and 18 F-FDG-PET can predict the status of TERT p mutations in IDH wt LGA. Histological grade can be a confounding factor to analyze molecular status in IDH wt LGA using advanced MRI sequences and 18 F-FDG-PET. Abstract: Purpose: The telomerase reverse transcriptase promoter ( TERT p) mutation is an unfavorable prognostic factor in isocitrate dehydrogenase-wildtype ( IDH wt) histologically lower-grade astrocytoma (LGA), which was incorporated as a key component in the WHO 2021 classification of IDH wt LGA, replacing histologic grades in the WHO 2016 classification. The purpose of this study was to identify the imaging characteristics predictive of TERT p mutations in IDH wt LGA. Methods: This retrospective study was approved by our institutional review board. This single-center study retrospectively included 59 patients with pathologically confirmed IDH wt LGA with known TERT p mutation status. In addition to clinical information and morphological characteristics, semi-quantitative imaging biomarkers such as the tumor-to-normal ratio (T/N ratio) on 18 F-FDG-PET, normalized apparent diffusion coefficient (nADC), and histogram parameters from normalized relative cerebral blood volume (nrCBV) maps were compared between (a) TERT p-wildtype and TERT p-mutant tumors or (b) grade II and grade III astrocytoma. A p value < 0.05 was considered significant. Results: There were no significant differences in the conventional imaging findings, T/N ratio on FDG-PET, nrCBV or ADC histogram metrics between IDH wt LGA with TERT p mutations and those without. Grade III IDH wt astrocytomas exhibited significantly higher nrCBV values, T/N ratio and lower ADC parameters than grade II IDH wt astrocytoma. Conclusions: In patients with IDH wt LGA, T/N ratio, nrCBV values and nADC may be surrogate markers for predicting histologic grade, but are not useful for predicting TERT p mutations.