Performance of multiparametric magnetic resonance imaging in the evaluation and management of clinically low-risk prostate cancer

Abstract

Objective The purpose of this article is to review the multiparametric magnetic resonance imaging (mMRI) of the prostate and MR-guided prostate biopsy, and their role in the evaluation and management of men with low-risk prostate cancer. Methods We performed a literature review based on the MEDLINE database search for publications on the role of mMRI (a) in detection and localization of prostate cancer, prediction of tumor aggressiveness and progression and (b) in guiding targeted prostate biopsy. Results The mMRI, particularly diffusion-weighted imaging with T2-weighted imaging, is a useful tool for tumor localization in low-risk prostate cancer as it can detect lesions that are more likely missed on extended biopsy schemes and can identify clinically significant disease requiring definitive treatment. The MR-guided biopsy of the most suspicious lesions enables more accurate and safer approach to guide enrollment into the active surveillance program. However, the MR-guided biopsy is complex. The fusion of MRI data with transrectal ultrasound for the purpose of biopsy provides a more feasible technique with documented accurate sampling. Conclusion Although the mMRI is not routinely used for risk stratification and prognostic assessment in prostate cancer, it can provide valuable information to guide management of men with low-risk disease. Incorporation of mMRI into the workup and monitoring of patients with low-risk prostate cancer can help discriminate clinically significant disease from indolent disease. Targeted biopsy of MR-suspicious lesions enables accurate sampling of potentially aggressive tumors that may affect outcomes.

Who Bears the Greatest Burden of Aggressive Treatment of Indolent Prostate Cancer?

“…6,31 Because there are no guarantees that men will not progress on surveillance and there are concerns of undersampling and undergrading/staging of low-risk disease, some men with higher access to care may be reluctant to pursue a surveillance strategy. 32 More accurate identification of precisely which men are appropriate for surveillance may lead to more widespread acceptance of deferred treatment among both patients and physicians. Specifically, methods for selecting those appropriate for surveillance for indolent disease could include more personalized risk stratification as afforded by tools such as the University of California, San Francisco Cancer of the Prostate Risk Assessment score, use of magnetic resonance imaging to rule out potentially higher-grade lesions that could be targeted for biopsy, and novel clinical and molecular markers as they become available.…”

“…Specifically, methods for selecting those appropriate for surveillance for indolent disease could include more personalized risk stratification as afforded by tools such as the University of California, San Francisco Cancer of the Prostate Risk Assessment score, use of magnetic resonance imaging to rule out potentially higher-grade lesions that could be targeted for biopsy, and novel clinical and molecular markers as they become available. 2,5,[32][33][34] Magnetic resonance imaging has a high specificity for low-risk prostate cancer, and currently available imaging techniques hold promise for improving patient selection for surveillance. 34 Likewise, currently available novel markers have the potential to improve current surveillance protocols, increase the number of patients suitable for surveillance, and reduce the burden of monitoring while on surveillance.…”

Magnetic Resonance-Guided Prostate Biopsy

“…32 In a prospective multicenter study of 63 men with low-risk PCa eligible for AS, initial MP-MR imaging and MR-GB were performed at the 3-and 12-month follow-up visits to assess risk reclassification. Surveillance TRUS biopsy could miss 10% of patients with unfavorable risk of disease and misclassify them as AS eligible.…”

Quantitative Graphical Analysis of Simultaneous Dynamic PET/MRI For Assessment of Prostate Cancer

“…The increased role in prostate cancer management of image guided biopsy and therapy, as well as of active surveillance, has created a critical need for accurate tumor localization using imaging[1–3]. MRI is increasingly being used for this purpose given the impact of multi-parametric imaging for improved diagnostic performance[3, 4], although is still prone to false-positive interpretations from such entities as prostatitis and benign prostatic hyperplasia, as well as false-negative interpretations in some tumors depending on tumor size, grade, and histologic architecture[5, 6].…”