Podium Session
Christopher Khoo, MD,MBBS
Imperial Prostate, Imperial College London
Presentation Authors: Christopher Charles Khoo*, David Eldred-Evans, Johannes Jaenicke, Mariana Bertoncelli Tanaka, Taimur Tariq Shah, Saiful Miah, Martin Connor, Deepika Reddy, Mohammed Noureldin, Joanne Sethi, Alexandra Forde, Heather Bhola-Stewart, Andrew Smith, James Carton, Josephine Lloyd, Ethna Mannion, Feargus Hosking-Jervis, Emma Cullen, Rufus Cartwright, Martin Clark, Manit Arya, David Hrouda, Mathias Winkler, Henry Tam, Hashim Uddin Ahmed, London, United Kingdom
Introduction: There remains lack of agreement on the optimal mpMRI prostate cancer scoring system with recent UK consensus recommending use of 5-point Likert assessment rather than PI-RADS. Using a paired cohort study design we compared clinical validity and utility of both scoring systems in the detection of clinically significant (cs) and insignificant (ci) prostate cancer (PCa).
Methods: 329 pre-biopsy mpMRI scans in consecutive patients underwent prospective paired reporting using both Likert and PI-RADS (v2) by expert uro-radiologists. Patients were offered biopsy for any Likert or PI-RADS score ≥3; a score of 3 required PSA-density ≥0.12ng/ml/ml. Utility was evaluated in terms of proportion biopsied, and proportion of csPCa and ciPCa detected. In those patients biopsied, overall accuracy of each system was assessed using receiver operating characteristic (ROC) curves. The primary threshold of csPCa was Gleason ≥3+4; secondary thresholds of ≥Gleason 4+3, Ahmed/UCL1 (Gleason ≥4+3 or maximum cancer core length (CCL) ≥6 or total CCL ≥6) and Ahmed/UCL2 (Gleason ≥3+4 or maximum CCL ≥4 or total CCL ≥6) were also used.
Results: Median age was 66 (IQR: 13) and PSA was 8 (IQR: 6). A similar proportion of men met the biopsy threshold and underwent biopsy in both groups (69.3% vs. 75.7%). Likert predicted more csPCa than PI-RADS across all disease thresholds. Rates of ciPCa were comparable in each group (Table 1). ROC analysis of biopsied patients showed that, although both scoring systems performed well as predictors of csPCa, Likert exhibited higher areas under the curve (AUC) than PI-RADS across all thresholds (Table 2).
Conclusions: Both scoring systems demonstrated good diagnostic performance. Overall, Likert was superior by all definitions of csPCa. It has the advantages of being flexible, intuitive and allows inclusion of clinical data. We recommend that its use be considered once radiologists have developed sufficient experience in reporting prostate mpMRI.
