68-year-old man. Radical prostatectomy 26 months ago: Gleason 4+3, pT3a N0 (0/14 nodes), negative margins; PSA undetectable after surgery. PSA now 0.42 ng/mL with a doubling time of 7 months. No hormone therapy. Request: ⁶⁸Ga-PSMA-11 PET/CT before salvage radiotherapy.
Step 1 · PSMA PET/CT
Focus 1 is a 6 mm node beside the left external iliac vessels, SUVmax 12. Blood pool SUVmean 1.4, liver SUVmean 5.3, parotid SUVmean 14. What is its PSMA expression score?