Purpose This retrospective study aimed to correlate 18F-FDG uptake on PET/CT with isocitrate dehydrogenase enzyme isoform 1 (IDH1) mutation in patients with cerebral gliomas. Hierarchical interactions between factors affecting overall survival (OS) were also examined. Methods In 59 patients with glioma, the ratio of the SUVmax of a glioma to the SUVmean of the contralateral cortex (G/C ratio) on 18F-FDG PET/CT and the presence of IDH1 mutation were correlated. The prognostic value of clinicopathologic factors and G/C ratio for OS were assessed using a Cox proportional hazards model and classification and regression tree models. Results The mean G/C ratio of IDH1-mutant tumors was significantly lower than that of IDH1 wild-type tumors (0.73 vs 1.14, P = 0.004). In multivariate analysis, IDH1-mutant and G/C ratio were significant for OS. The classification and regression tree modeling identified 3 risk groups for OS (group 1: IDH1 mutant [hazard ratio, 0.2]; group 2: G/C ratio ≤0.8 with IDH1 wild type [hazard ratio, 0.83]; group 3: G/C ratio >0.8 with IDH1 wild type [hazard ratio, 1.9]) (overall P < 0.001). The mean OS was 37.0 months in group 1, 28.6 months in group 2, and 20.7 months in group 3, respectively, showing significant differences among the groups (group 1 vs group 2: P = 0.023, group 2 vs group 3: P = 0.049, group 1 vs group3: P < 0.001). Conclusions 18F-FDG uptake of IDH1-mutant gliomas was significantly lower than that of IDH1 wild-type gliomas. IDH1 mutation was the most important factor in identifying patients with the best prognosis, whereas increased 18F-FDG uptake provided additional prognostic information for predicting poor OS among patients with IDH1 wild-type gliomas.
Bibliographical noteFunding Information:
Received for publication November 5, 2017; revision accepted January 21, 2018. From the Departments of *Nuclear Medicine, †Pathology, and ‡Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea. Conflicts of interest and sources of funding: This work was supported partially by a National Research Foundation of Korea grant funded by the Korean government (MSIP) (NRF-2011-0030086) and the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Science and ICT (NRF-2012R1A1A3008042 and NRF-2016R1E1A1A01943303). None declared to all authors. All procedures involving human participants were performed in accordance with the ethical standards of the institutional research committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. Formal consent was not required for this type of study. The institutional review board of our university approved this retrospective study, and the requirement to obtain informed consent was waived. Correspondence to: Mijin Yun, MD, PhD, Department of Nuclear Medicine, Severance Hospital, 50-1 Yonsei-Ro, Seodaemun-Gu, Seoul 120-752, South Korea. E-mail: email@example.com. Supplemental digital content is available for this article. Direct URL citation appears in the printed text and is provided in the HTML and PDF versions of this article on the journal’s Web site (www.nuclearmed.com). Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved. ISSN: 0363-9762/18/4305–0311 DOI: 10.1097/RLU.0000000000002006
All Science Journal Classification (ASJC) codes
- Radiology Nuclear Medicine and imaging