Patients with suspected prostate cancer are often under diagnosed or misclassified and the clinical priority is for increased prostate cancer identification/localization, with MRI directed biopsies increasing the improved detection of clinically significant prostate cancer. Alternatively, those with suspected prostate cancer are at risk of over-diagnosis. Prostate multiparametric MRI may decrease the number of unnecessary biopsies, decrease the risk of detection of clinically insignificant prostate cancer and improve risk stratification. Both the NCCN and EAU/EANM/ESTRO/ESUR/SIOG guidelines for prostate cancer recommend prostate multiparametric MRI before biopsy among men with suspected prostate cancer.
Among patients with localized prostate cancer, the majority of men with low-risk disease will not die from prostate cancer and prostate multiparametric MRI can be used in conjunction with active surveillance algorithms. This reduces the number of biopsies and reduces treatment of insignificant prostate cancer. Among men with intermediate-risk localized prostate cancer, there is currently poor identification of a favorable subgroup of men. Prostate multiparametric MRI is now being implemented into treatment planning of these men by discriminating low/high volume prostate cancer and identifying adverse features for appropriate treatment. Men with high-risk prostate localized prostate cancer currently have poor clinical T and N staging. The clinical priority of prostate multiparametric MRI is to improve TNM staging (visualizing T3b-T4 disease), help plan treatment planning (for surgery and radiotherapy), and help select patients for initial primary therapy.
According to the recently published ASCO guideline on optimum imaging for advanced prostate cancer, ASCO recommends that clinicians should take into consideration advanced imaging if the results will alter disease states, change the clinical scenario, or guide/change treatment.1 Currently, conventional imaging (CT/bone scan) are poor at risk-stratifying patients, which may provide an opportunity for next-generation imaging to add clinical benefit, although prospective data are limited. Next-generation imaging may be offered to patients for clarification of equivocal findings or detection of additional sites of disease.
For patients with biochemical recurrence, the clinical priority is for avoiding unnecessary treatment. As such, it is important to rule out systemic disease and rule in local disease with prostate multiparametric MRI. Furthermore, PSMA-PET CT is recommended for men with PSA > 0.2 to staging for M+ disease. Options for salvage local therapy require proof of disease, for which prostate multiparametric MRI may be used for restaging the M0 patient – visible disease can be target (plus systematically) biopsied.
Dr. Schoots concluded with several take home messages from his presentation:
- Prostate multiparametric MRI will change detection/classification of prostate cancer, staging, pre-treatment risk stratification, pre-treatment planning, and recurrence treatment
- Prostate multiparametric MRI in localized disease will revolutionize proportion of disease state and the current management of prostate cancer
1. Trabulsi EJ, Rumble RB, Jadvar H, et al. Optimum Imaging Strategies for Advanced Prostate Cancer: ASCO Guideline. J Clin Oncol 2020 Jan 15 [Epub ahead of print].
Presented by: Ivo Schoots, MD, PhD, Assistant Professor and Principal Investigator of Abdominal Imaging, Erasmus University Medical Center, Rotterdam, Netherlands
Written by: Zachary Klaassen, MD, MSc – Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia Twitter: @zklaassen_md at the 2020 Genitourinary Cancers Symposium, ASCO GU #GU20, February 13-15, 2020, San Francisco, California