J Urol 2017 04 19;197(4):1006-1013. Epub 2016 Nov 19.
Division of Surgery and Interventional Science (CMM, NLR, AD, AJR, HUA, MA, ME), University College London, United Kingdom; Biostatistics Group, University College London Hospitals/University College London Research Support Centre (FJ, GA), University College London, United Kingdom; Department of Urology, University College London Hospitals National Health Service Foundation Trust (CMM, NLR, AD, AJR, HUA, MA, NM, ME), United Kingdom; Department of Radiology (FG, CA), University College London Hospital Trust, United Kingdom; Department of Pathology (AF, CJ), University College London Hospital Trust, United Kingdom; Department of Urology, Charing Cross Hospital, Imperial College National Health Service Trust (MW), United Kingdom; Department of Clinical Oncology, University College Hospital London (AVM), United Kingdom; Klarismo (BJW), United Kingdom; Department of Mathematics, Imperial College London (BJW), United Kingdom; Department of Urology, Frimley Park Hospital, Surrey (SRJB), United Kingdom; GlaxoSmithKline Research and Development (RC), Philadelphia, Pennsylvania; Institut National de la Santé et de la Recherche Médicale, U1099 and Laboratoire Traitement du Signal et de l'Image, Université de Rennes 1, Rennes (GG), France.
Purpose: Dutasteride, which is licensed for symptomatic benign prostatic hyperplasia, has been associated with a lower progression rate of low risk prostate cancer. We evaluated the effect of dutasteride on prostate cancer volume as assessed by T2-weighted magnetic resonance imaging.
Materials And Methods: In this randomized, double-blind, placebo controlled trial, men with biopsy proven, low-intermediate risk prostate cancer (up to Gleason 3 + 4 and PSA up to 15 ng/ml) who had visible lesion of 0.2 ml or greater on T2-weighted magnetic resonance imaging sequences were randomized to daily dutasteride 0.5 mg or placebo for 6 months. Lesion volume was assessed at baseline, and 3 and 6 months with image guided biopsy to the lesion at study exit. The primary end point was the percent reduction in lesion volume over 6 months. This trial was registered with the European Clinical Trials register (EudraCT 2009-102405-18).
Results: A total of 42 men were recruited between June 2010 and January 2012. In the dutasteride group, the average volumes at baseline and 6 months were 0.55 and 0.38 ml, respectively and the average reduction was 36%. In the placebo group, the average volumes at baseline and 6 months were 0.65 and 0.76 ml, respectively, and the average reduction was -12%. The difference in percent reductions between the groups was 48% (95% CI 27.4-68.3, p <0.0001). The most common adverse event was deterioration in erectile function, which was 25% in men randomized to dutasteride and 16% in men randomized to placebo.
Conclusions: Dutasteride was associated with a significant reduction in prostate cancer volume on T2-weighted magnetic resonance imaging compared to placebo.