DOI: 10.1007/s00259-018-4160-7Pages: 1-11

Improved specificity with 68Ga PSMA PET/CT to detect clinically significant lesions “invisible” on multiparametric MRI of the prostate: a single institution comparative analysis with radical prostatectomy histology

1. Royal Brisbane and Women’s Hospital, Department of Urology

2. The University of Queensland, Faculty of Medicine

3. Royal Brisbane and Women’s Hospital, Department of Nuclear Medicine

4. Griffith University

5. Edith Cowan University

Correspondence to:
John Yaxley
Tel: +61 7 3646 1711
Email: john@wesleyurologyclinic.com.au

Close

Abstract

Purpose

Positron emission tomography (PET) for prostate-specific membrane antigen (PSMA) represents a promising method for prostate cancer diagnosis and staging. Comparisons of PSMA-based tumour characterisation to multiparametric MRI (mpMRI) are limited, hence this study sought to compare the diagnostic accuracy of 68Ga-PSMA PET/CT to mpMRI against radical prostatectomy (RP) whole gland histopathology.

Methods

A retrospective cohort study of consecutive patients who underwent pre-operative mpMRI and 68Ga-PSMA PET/CT followed by a RP was performed. Standard clinical parameters were collected. “Per patient” and “per lesion” analyses for image-based detection according to RP histopathology were described using sensitivity, specificity and other measures of diagnostic accuracy.

Results

Fifty-eight patients (median age 65.5 years, median PSA 7.35 ng/mL) underwent RP, resulting in a high-risk cohort (≥pT3 69%). Sensitivities for identification of index lesion, bilateral and multifocal disease were 90%, 21%, 19% for mpMRI and 93%, 42%, 34% for 68Ga-PSMA PET/CT. Histology analyses revealed 88 cancer foci of Gleason grades 3 + 3 (4%), 3 + 4 (64%), 4 + 3 (19%), 4 + 4 (3%) and ≥ 4 + 5 (10%), of which 68Ga-PSMA PET/CT correctly detected more foci (78%, AUC 0.817) than mpMRI (69%, AUC 0.729).

Conclusions

68Ga-PSMA PET/CT may better reflect RP histopathology compared to mpMRI when considering multifocal and bilateral disease. These findings may influence surgical planning, targeted biopsy and focal therapy strategies and require further research.

To access the full text, please Sign in

If you have institutional access, please click here

  • Accepted: Sep 5, 2018
  • Online: Sep 19, 2018

Article Tools

eanm
EJNMMI Ad