Login to Access Video or Poster Abstract: MP20-15
Sources of Funding: This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University, under project number 3264.

Introduction

PSMA/PET CT is a novel molecular imaging for accurate staging of prostate cancer. Its role has been mostly investigated in post-treatment setting. We assessed the diagnostic accuracy of 68Gallium-PSMA PET to predict LN metastases in primary N-staging in high and_x000D_ very high-risk non-metastatic prostate cancer in comparison with morphologic imaging.

Methods

This was a multi-centric trial of the Society of Urologic Oncology in Turkey in conjunction with Nuclear Medicine Department at Cerrahpasa School of Medicine, Istanbul University. Patients were accrued from 8 centers. High and very high-risk patients_x000D_ scheduled to undergo surgical treatment with extended LN dissection between July 2014 and October 2015 were included. Morphological imaging was with either MRI/CT. PSMA PET-CT was performed and evaluated at a single center. Sensitivity, specificity and accuracy_x000D_ were calculated for the detection of lymphatic metastases for PSMA PET/CT and morphological imaging. Kappa values were calculated for pathological and radiological incidence of LN metastases.

Results

Data on 51 eligible patients are presented. Sensitivity, specificity and accuracy of PSMA PET to detect LN metastases in primary setting were 53%, 86%, and 76% and increased to 67%, 88% and 81% in a sub-group with ?15 LN removed. Kappa values for correlation of imaging and pathology was 0.41 for PSMA PET and 0.18 for morphological_x000D_ imaging.

Conclusions

PSMA/PET CT is superior to morphological imaging for the detection of metastatic LNs in primary prostate cancer setting. Surgical dissection remains to be the gold standard for precise lymphatic staging.

Funding

This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University, under project number 3264.