OBJECTIVE: To investigate the value of Dynamic Contrast Enhanced-Ultrasound (DCE-US) and software-generated parametric maps in predicting biopsy outcome and their potential to reduce the amount of negative biopsy cores.
PATIENTS AND METHODS: For 651 prostate biopsy locations (82 consecutive patients) we correlated the interpretation of DCE-US recordings with and without parametric maps with biopsy results. The parametric maps were generated by software that extracts perfusion parameters that differentiate benign from malignant tissue form DCE-US recordings. We performed a stringent analysis (all tumours) and a clinical analysis (clinically significant tumours). We calculated the potential reduction in biopsies (benign on imaging) and the resultant missed positive biopsies (false negatives). Additionally, we evaluated the performance in terms of sensitivity, specificity NPV, and PPV on the per-prostate level.
RESULTS: Based on DCE-US, 470/651 (72.2%) of biopsy locations appeared benign resulting in 40 false negatives (8.5%) regarding clinically significant tumour only. Including parametric maps, 411/651 (63.1%) of the biopsy locations appeared benign, resulting in 23 false negatives (5.6%). In the per-prostate clinical analysis, DCE-US classified 38/82 prostates as benign, missing 8 diagnoses. Including parametric maps, 31/82 prostates appeared benign, missing 3 diagnoses. Sensitivity, specificity, PPV and NPV were 73%, 58%, 50% and 79% for DCE-US alone and 91%, 56%, 57% and 90% with parametric maps, respectively.
CONCLUSION: DCE-US interpretation with parametric maps allows good prediction of biopsy outcome. A two-thirds reduction in biopsy cores seems feasible with only a modest decrease in cancer diagnosis.
Postema A, Frinking P, Smeenge M, De Reijke T, De la Rosette J, Tranquart F, Wijkstra H. Are you the author?
Department of Urology, Academic Medical Center, Amsterdam, The Netherlands.
Reference: BJU Int. 2015 Mar 6. Epub ahead of print.