The Role of 18F-PSMA PET in Prostate Cancer Diagnosis in Equivocal MRI

The Role of 18F-PSMA PET in Prostate Cancer Diagnosis in Equivocal MRI: a Multi-center Randomised Controlled Trial

This study is a multi-center RCT to compare the clinically significant prostate cancer (csPCa) detection and/or change in clinical management in MRI guided (MRI arm) biopsy and MRI+18F-PSMA guided (Combined arm) biopsies in men with equivocal MRI prostate scans. If additional clinical value is shown by adding 18F-PSMA PET to equivocal MRI, then this should be the new standard of care.

The investigators propose to conduct a phase III multi-center randomised controlled trial to evaluate the detection of clinically significant prostate cancer (csPCa) by MRI-guided biopsy approach (MRI arm) versus MRI+PSMA approach (COMBINED arm). Clinically significant prostate cancer (csPCa) is defined as prostate cancer classified as ISUP (International Society of Urogenital Pathology) Grade group 2 or higher. Patients with clinical suspicion of prostate cancer on MRI with PI-RADS (Prostate Imaging-Reporting and Data System, version 2.1) score 2 with red flag (PSA density >0.2 OR Prostate health index, PHI>35), PI-RADS 3, or PI-RADS 4 (and PSAd <0.1 OR PHI<35) will be randomised in a 1:1 manner to MRI arm or COMBINED arm. The detection rates of csPCa will be compared between arms. The study hypothesis is that COMBINED arm is superior to MRI arm in detecting csPCa and changing clinical management.

Inclusion Criteria:

• Men ≥18 years of age

• Serum Prostate-specific antigen (PSA) 4-15 ng/mL, repeated at least once

• Prostate mpMRI done within 6 months

• MRI prostate with PI-RADS (11) scores of:

  • PI-RADS score 2 with red flag (PSA density >0.2 OR Prostate health index, PHI>35),
  • PI-RADS 3, OR
  • PI-RADS 4 with lower csPCa risks (PSAd <0.1 OR PHI<35)

• Normal Digital rectal examination

• Patient agrees for targeted and systematic prostate biopsy

Exclusion Criteria:

• Prostate biopsy within past 5 years
• Past or current history of prostate cancer
• Contraindicated to undergo PSMA PET-CT scan
• Contraindicated to prostate biopsy: active urinary tract infection, fail insertion of transrectal ultrasound probe into rectum (abdominal perineal resection, anal stenosis), fail to be placed in lithotomy position, uncorrectable coagulopathy, antiplatelet or anticoagulant which cannot be stopped (keep aspirin before and after biopsy is permitted)