AUA 2017: Evaluation of Prebiopsy Magnetic Resonance Imaging Combined with Prostate-Specific Antigen Density in the Diagnosis of Prostate Cancer in Men Aged 75 Years and Older with Elevated PSA
The authors used 141 patients over the age of 75 who underwent a prebiopsy MRI at their institution in Tokyo, Japan and compared MRI findings to biopsy pathological reports, as well as incorporating PSA density into models. Among these men, 73% were diagnosed with prostate cancer. For the 38 men without prostate cancer, 30 patients were deemed on prebiopsy MRI to have suspicion for prostate cancer, but subsequent prostate biopsy was negative, leading to a specificity of 21%. Furthermore, among these 30 false positive MRI cases, prostate biopsy may have been avoided if a MRI-based transitional zone-PSA density cut-off value of 0.42 were considered. When the authors stratified the prostate cancer-positive group according to Gleason score (GS ≤6, 7, and ≥8), the accuracy of MRI for detecting GS ≤6 was 84.6%, 91.7% for GS 7 disease, and 96.7% for GS ≥8 prostate cancer. A limitation of the study is the relatively small sample size.
In summary, the authors conclude that using PSA density with a prostate MRI may help with selecting patients older than 75 years of age that should undergo a prostate biopsy. Certainly, the question remains whether these patients, given their age, should be considered for a prostate biopsy in the first place. This study design should be considered in younger patients who would perhaps derive more benefit from a prostate biopsy and potential prostate cancer diagnosis.
References:
Ahmed HU, El-Shater Bosaily A, Brown LC, et al. Diagnostic accuracy of multi-parametric MRI and TRUS biopsy in prostate cancer (PROMIS): A paired validating confirmatory study. Lancet 2017;389:815-822.
Speaker: Yoshinori Yanai, Keio University School of Medicine, Tokyo, Japan
Co-Authors: Takeo Kosaka, Yu Teranishi, Seiya Hattori, Kazuhiro Matsumoto, Shinya Morita, Kazunobu Shinoda, Toshiaki Shinojima, Ryuichi Mizuno, Eiji Kikuchi, Shuji Mikami, Masahiro Jinzaki, Akira Miyajima, Mototsugu Oya
Written By: Zachary Klaassen, MD, Urologic Oncology Fellow, University of Toronto, Princess Margaret Cancer Centre
Twitter: @zklaassen_md
at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA