68Ga-PSMA PET/CT in Recurrence Prostate Cancer. Should We Perform Delayed Image in Cases of Negative 60 Minutes Postinjection Examination?

We report a case of a 59-year-old man with prostate adenocarcinoma, Gleason score 9 after prostatectomy and adjuvant radiotherapy. The patient showed biochemical recurrence. On standard Ga-PSMA PET/CT examination, 60 minutes postinjection, the PET/CT images showed only trace accumulation in the ureters. To identify lesions close to the ureters, imaging of the pelvis was performed 2 hours postinjection. The delayed image showed clearly visible increased uptake in a right internal iliac lymph node that was normal-sized by CT. The patient underwent radiotherapy with planning based on the Ga-PSMA PET/CT image. Follow-up testing showed prostate-specific antigen level reduction to 0.04 ng/mL.