Login to Access Video or Poster Abstract: MP18-08
Sources of Funding: National Institutes of Health_x000D_ Blue Earth Diagnostics Limited supplied fluciclovine cassettes for the study.

Introduction

To compare the diagnostic performance of PET-CT using the synthetic amino acid radiotracer fluciclovine with multiparametric magnetic resonance imaging (mpMRI) in recurrent prostate cancer.

Methods

24 patients with biochemical failure after non-prostatectomy definitive therapy underwent fluciclovine PET-CT and mpMRI (T2, DWI and DCE) within 29 days with blinded interpretation by expert readers. Reference standard was established via histology and clinical follow-up. Diagnostic performance was calculated for each of 2 readers for PET-CT (P1 and P2) and 2 other readers for MRI (M1 and M2). For the purpose of this analysis, equivocal interpretations were analyzed as negative.

Results

In the prostate, 22 patients underwent biopsy with 13 malignant and 9 benign (2 not biopsied). Accuracy for PET was 63.6% for both readers. Accuracy for mpMR was 45.5% and 40.9% for readers M1 and M2, respectively. Overall, fluciclovine PET had higher sensitivity for both readers while mpMR had higher specificity (Figure 1a)._x000D_ _x000D_ 17 patients met the reference standard for extraprostatic disease detection. 7 of these were confirmed by histology and 10 by clinical follow-up. Accuracy for PET was 88.24% for both readers. Accuracy for mpMR was 52.94% and 70.79% for readers M1 and M2, respectively. Overall, fluciclovine PET had higher sensitivity and specificity compared to mpMR (Figure 1b)._x000D_ _x000D_ Inter-reader agreement for fluciclovine PET was 91.6% in the prostate and 87.5% for extraprostatic disease detection. For mpMRI, inter-reader agreement was 37.5% and 75% respectively for prostate and extraprostatic disease detection.

Conclusions

Although fluciclovine PET-CT had higher sensitivity in the prostate, MRI had higher specificity for disease detection. However for extraprostatic disease, fluciclovine had higher sensitivity and specificity. Inter-reader agreement was better with fluciclovine PET-CT compared with mpMR.

Funding

National Institutes of Health_x000D_ Blue Earth Diagnostics Limited supplied fluciclovine cassettes for the study.