Abstract
We report a case in which 18F-FDG PET was able to discriminate pseudoprogression from progression observed on contrast-enhanced (CE) MRI (CE-MRI). A 56-year-old male patient with anaplastic oligodendroglioma demonstrated markedly increased tumor enhancement on CE-MRI 1 month after completing radiation therapy (RT), suggesting radiological progression. However, the patient was clinically improved and therefore received an early-therapy response assessment PET to assess for pseudoprogression. PET showed low tumor uptake indicating stable disease. Follow-up CE-MRI at 3 and 4 months post-RT confirmed stable disease. This case emphasizes the value of 18F-FDG PET when pseudoprogression is clinically suspected.
Keywords: pseudoprogression, anaplastic oligodendroglioma, 18F-FDG, PET, therapy response assessment
Acknowledgments
Conflicts of interest and sources of funding: This work was supported by the US National Institutes of Health research grant U01 CA140230 and UPCI shared resources award P30CA047904.
Footnotes
Institution where work was performed: Department of Radiology, University of Pittsburgh, Pittsburgh, PA.
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