To retrospectively investigate the uptake of 18F-fluciclovine on PET/CT in patients with suspected recurrent high-grade glioma (HGG).
Twenty-one patients were included. The standard of truth was histopathologic interpretation if available. When histopathology was not available or rebiopsy did not show signs of malignancy, clinical follow-up including MRI and clinical outcome was considered the standard of truth.
All 21 patients met the reference standard of either histopathologic proof of HGG recurrence (n = 10) or disease progression clinically and with tumor growth corresponding to the primary tumor sites on follow-up MRI (n = 11). Median time from PET/CT to death was 5 months (range, 1–20 months). Median time from primary diagnosis to death was 14.5 months (range, 6 to >400). Average SUVmax of the lesions was 8.3 ± 5.3 (SD) and 0.34 ± 0.13 for normal brain tissue. Median lesion-to-background ratio was 21.6 (range, 3.1–84.4). In 4 patients, 18F-fluciclovine PET/CT detected small satellite tumors that had not been reported on MR.
The uptake of 18F-fluciclovine in clinically and/or histopathologically confirmed recurrent HGG is high compared with the uptake reported for other amino acid PET tracers. Because of the high tumor uptake and thus high tracer contrast, small satellite tumors with a diameter below usual reported PET spatial resolution and not reported on MRI were detected in 4 patients. As no patients with confirmed treatment-related changes were included, we cannot as of yet ascertain the ability of 18F-fluciclovine PET to discriminate between recurrent HGG and treatment-related changes, for example, pseudoprogression and radionecrosis.
From the *Department of Nuclear Medicine, Oslo University Hospital, Oslo, Norway
†Department of Nuclear Medicine and PET-Centre, Aarhus University Hospital, Aarhus
‡The Faculty of Health, Aarhus University, Aarhus, Denmark
§Department of Nuclear Medicine and PET-Centre, University Hospital of North Norway, Tromso
∥Department of Oncology, Oslo University Hospital
¶Section for Cancer Cytogenetics, Institute for Cancer Genetics and Informatics, Oslo University Hospital
**Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo
††Department of Pathology, Oslo University Hospital, Oslo, Norway.
Received for publication September 7, 2018; revision accepted April 11, 2019.
Conflicts of interest and sources of funding: Blue Earth Diagnostics Ltd, marketer of 18F-fluciclovine (Axumin), has supported research funding to Oslo University Hospital, Oslo, Norway, for clinical studies using 18F-fluciclovine PET/CT in prostate cancer performed by the authors T.V.B. and T.B.-G. T.B.-G. has received honorarium from Blue Earth Diagnostics Ltd for giving user training lectures on 18F-fluciclovine in prostate cancer in June and November 2018. No financial support has been received for this retrospective registry study. Concerning this study, there is nothing to disclose for any of the authors.
Correspondence to: Trond V. Bogsrud, MD, PhD, University Hospital of North Norway, Sykehusvegen 38, 9019 Tromsø, Norway. E-mail: Trond.Bogsrud@unn.no.
Online date: June 14, 2019