Publications

Abstract

OBJECTIVES:: To determine the predictive and diagnostic value of (68)Ga-HBEDD PSMA-11 PET/CT (PSMA) for surgical response in males with prostate cancer prior to radical prostatectomy. METHODS:: We analysed results of 142 males with staging PSMA prior to radical prostatectomy (RP). Data collected included PSMA PET/CT, bone scan (30/142), mpMRI (112/142), and pathological T stage (pT) stage, Gleason score, surgical margins and lymph node status at RP. Prostate-specific antigen (PSA) was documented at staging scan, and following surgery (median 45 days (IQR 38-59). A PSA of < 0.03 ng ml(-1) was classified as surgical response (SR). Logistic regression was performed for association of pre-operative clinical variables and SR. RESULTS:: 97.9% (139/142) of males had positive intra prostatic findings on PSMA. 14.1 % (20/142) of males had further sites of extra prostatic disease identified on PSMA PET. In males with disease confined to the prostate, 82.9 % (92/111) achieved a SR, compared to 28.6 % (4/14) in males with extra prostatic disease identified (lymph node positive and distant metastatic disease) (p < 0.001). On binary logistic regression PSMA had a superior predictive value for SR than Gleason score, PSA (at time of imaging) or pT stage. MRI was less sensitive and more specific for seminal vesicle involvement (SVI), and less sensitive for nodal involvement. CONCLUSION:: Extra prostatic disease identified on staging pre-operative PSMA PET is independently predictive of a poor surgical response to RP, and may indicate a need for a multimodality approach to treatment. ADVANCES IN KNOWLEDGE:: This is one of the first studies to correlate the PSMA PET's staging capacity to prostate cancer patient's outcomes to radical prostatectomy and indicates it's potential in predicting which patients will benefit from radical prostatectomy.