Pseudoprogression on 68Ga-Prostate-Specific Membrane Antigen-11 PET/CT in a Treated Glioblastoma

After standard treatment of glioblastoma, pseudoprogression versus true progression is a clinical challenge. Indeed, to differentiate these 2 on contrast MRI (cMRI) is problematic. In recent time, Ga-prostate-specific membrane antigen-11 (Ga-PSMA) PET/CT has been suggested to have high accuracy in glioblastoma recurrence. We present a case of a 40-year-old man with right frontotemporal glioblastoma underwent surgery and radiotherapy. One month posttreatment cMRI showed a new enhancing lesion in the right hippocampal region, which was also positive on Ga-PSMA-11 PET/CT. On follow-up with conservative management, both cMRI and Ga-PSMA-11 PET/CT showed regression in new lesion, hence suggest pseudoprogression.