METHODS: We did this multicentre, paired-cohort, confirmatory study to test diagnostic accuracy of MP-MRI and TRUS-biopsy against a reference test (template prostate mapping biopsy [TPM-biopsy]). Men with prostate-specific antigen concentrations up to 15 ng/mL, with no previous biopsy, underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsy. The conduct and reporting of each test was done blind to other test results. Clinically significant cancer was defined as Gleason score ≥4 + 3 or a maximum cancer core length 6 mm or longer. This study is registered on ClinicalTrials.gov, NCT01292291.
RESULTS: Between May 17, 2012, and November 9, 2015, we enrolled 740 men, 576 of whom underwent 1·5 Tesla MP-MRI followed by both TRUS-biopsy and TPM-biopsy. On TPM-biopsy, 408 (71%) of 576 men had cancer with 230 (40%) of 576 patients clinically significant. For clinically significant cancer, MP-MRI was more sensitive (93%, 95% CI 88-96%) than TRUS-biopsy (48%, 42-55%; p<0·0001) and less specific (41%, 36-46% for MP-MRI vs 96%, 94-98% for TRUS-biopsy; p<0·0001). 44 (5·9%) of 740 patients reported serious adverse events, including 8 cases of sepsis.
CONCLUSION: Using MP-MRI to triage men might allow 27% of patients avoid a primary biopsy and diagnosis of 5% fewer clinically insignificant cancers. If subsequent TRUS-biopsies were directed by MP-MRI findings, up to 18% more cases of clinically significant cancer might be detected compared with the standard pathway of TRUS-biopsy for all. MP-MRI, used as a triage test before first prostate biopsy, could reduce unnecessary biopsies by a quarter. MP-MRI can also reduce over-diagnosis of clinically insignificant prostate cancer and improve detection of clinically significant cancer.
Lancet. 2017 Feb 25;389(10071):815-822. doi: 10.1016/S0140-6736(16)32401-1. Epub 2017 Jan 20.
Ahmed HU1, El-Shater Bosaily A2, Brown LC3, Gabe R4, Kaplan R3, Parmar MK3, Collaco-Moraes Y3, Ward K3, Hindley RG5, Freeman A6, Kirkham AP7, Oldroyd R8, Parker C9, Emberton M2; PROMIS study group.
1 Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London, UK; Department of Urology, UCLH NHS Foundation Trust, London, UK.
2 Division of Surgery and Interventional Science, Faculty of Medical Sciences, University College London, London, UK; Department of Urology, UCLH NHS Foundation Trust, London, UK.
3 MRC Clinical Trials Unit at UCL, London, UK.
4 Hull York Medical School and Department of Health Sciences, University of York, UK.
5 Department of Urology, Hampshire Hospitals NHS Foundation Trust, UK.
6 Department of Histopathology, UCLH NHS Foundation Trust, London, UK.
7 Department of Radiology, UCLH NHS Foundation Trust, London, UK.
8 Public and patient representative, Nottingham, UK.
9 Department of Academic Urology, Royal Marsden Hospital, Sutton, UK.