Presented by: Ofer Gofrit MD. PhD
Hadassah Hebrew University Hospital

Introduction

Current guidelines suggest that the indication for pelvic LN dissection (PLND) during radical prostatectomy (RP) should rely on nomograms predicting their involvement. PET/CT with prostate specific membrane antigen (PSMA) radioligand is gaining acceptance as routine diagnostic test before RP in patients with intermediate/high-risk prostate cancer (PC). In this study we examined the effect of preoperative PET/CT on the accuracy of the nomograms. 

Materials

Patients with  intermediate/high risk PC with PET/CT- PSMA showing no extra prostatic disease underwent RP with PLND and were followed postoperatively for at least 6 months. Reevaluation with PET/CT-PSMA was done in patients with detectable (>0.1 ng/ml) postoperative PSA levels. Minimal postoperative follow-up was 6 months.

Results

,

A total of 70 patients underwent RP for intermediate (34 patients) or high-risk disease (36 patients). According to the Partin, MSKCC and Briganti 2012 nomograms, in this case-mix, positive LNs were expected in 7, 13, and 12 patients, respectively. At PLND, one positive LN was found in a single patient (p<0.05 compared to the expected number of patients from all nomograms). Post-operatively, 10 patients developed detectable PSA levels. Radioligand uptake that could indicate LN involvement was noted in one patient. Considering these two patients as failures, the negative predictive value of PSMA-PET/CT for predicting LN involvement is 97.1%.

Conclusion

Pre-operative PSMA-PET/CT with no extra-prostatic uptake prior to RP in patients with intermediate to high-grade PC is highly accurate for ruling out LN involvement, superior to the routinely used nomograms. Its use induced stage migration, rendering predicting nomograms irrelevant.

Funding

None

Co-Authors

Marina Orevi, MD
Hadassah Hebrew UniversityHospital

Simona Ben Haim, MD
Hadassah Hebrew University Hospital

Tzahi Neuman, MD
Hadassah Hebrew University Hospital

Nordechai Duvdevani, MD
Hadassah Hebrew University Hospital

Guy Hidas, MD
Hadassah Hebrew University Hospital

Vkadimir Yutkin, MD
Hadassah Hebrew University Hospital