As a reminder, prostate MRI has 3 components
- T2 weighted imaging – provides detail re: anatomy
- Diffusion weighted imaging – provides detail re: cellularity
- Dynamic contrast enhanced imaging – provides detail re: vascularity
The current EAU guidelines recommend that an MRI is performed prior to a confirmatory biopsy (strong recommendation) and that repeat biopsies should be performed if there is any evidence of radiographic progression on multiparametric MRI (strong recommendation).
Stavrinides et al. demonstrated that MRI visible lesions impact event-free survival. In an institutional study of GG1-2 men on AS between 2004-2017, with a median follow-up of 58 months, they found that independent of GG, a visible MRI lesion at the time of inclusion was predictive of prostate cancer treatment, transition to WW, upgrading or death (compositely defined as “event”).
Additional work by Algohary et al.2 demonstrated 10 radiologic features that could be used to construct 3 machine-learning models to evaluate and identify clinically significant prostate cancer. Seven were T2 weighted imaging features and 3 were ADC based.
Using this data to then follow lesions in men on AS led to work by Moore et al.3, which developed the PRECISE recommendations. Key recommendations of the working group included reporting the index lesion size using absolute values at baseline and at each subsequent MRI. They also recommended that radiologists should assess the likelihood of true change over time (ie, change in size or change in lesion characteristics on one or more sequences) on a 1-5 scale. A checklist of items for reporting a cohort of men on active surveillance was developed, and can be seen below.
Following its publication, 5 different groups published the PRECISE criteria for their AS cohorts. Giganti et al.4 summarize this. The main differences between the cohorts were inclusion criteria, follow-up schedule, routine use of confirmatory biopsy, absence of contrast at follow-up imaging, use of PIRADS score, and definition of progression. Despite that, “all studies draw the same conclusion: patients with stable MRI (ie, PRECISE 1–3) and stable prostate-specific antigen (PSA) kinetics should avoid routine repeat biopsy.”
But Rajwa et al.5, in their systematic review, conclude that serial prostate MRI alone in patients on AS cannot accurately rule out or rule in prostate cancer progression – other clinical factors and biomarkers along with serial MRI are required to safely tailor frequency of biopsies.
Based on this, Dr. Giganti concludes that there needs to be further initiatives to better understand the tumor microenvironment and growth rate, radiomics and radiogenomics. But, ultimately, there also needs to be standardization (PRECISE criteria) and good quality MRI for it to be effective as a tool to monitor patients on AS.
Presented by: Francesco Giganti, MD, PhD, University College London, London, UK
Written by: Thenappan (Thenu) Chandrasekar, MD – Urologic Oncologist, Assistant Professor of Urology, Sidney Kimmel Cancer Center, Thomas Jefferson University, @tchandra_uromd on Twitter during the 2021 European Association of Urology, EAU 2021- Virtual Meeting, July 8-12, 2021.
References:
- Stavrinides V, Giganti F, Trock B, Punwani S, Allen C, Kirkham A, Freeman A, Haider A, Ball R, McCartan N, Whitaker H, Orczyk C, Emberton M, Moore CM. Five-year Outcomes of Magnetic Resonance Imaging-based Active Surveillance for Prostate Cancer: A Large Cohort Study. Eur Urol. 2020 Sep;78(3):443-451. doi: 10.1016/j.eururo.2020.03.035. Epub 2020 Apr 30. PMID: 32360049; PMCID: PMC7443696.
- Algohary A, Viswanath S, Shiradkar R, Ghose S, Pahwa S, Moses D, Jambor I, Shnier R, Böhm M, Haynes AM, Brenner P, Delprado W, Thompson J, Pulbrock M, Purysko AS, Verma S, Ponsky L, Stricker P, Madabhushi A. Radiomic features on MRI enable risk categorization of prostate cancer patients on active surveillance: Preliminary findings. J Magn Reson Imaging. 2018 Feb 22:10.1002/jmri.25983. doi: 10.1002/jmri.25983. Epub ahead of print. PMID: 29469937; PMCID: PMC6105554.
- Moore CM, Giganti F, Albertsen P, Allen C, Bangma C, Briganti A, Carroll P, Haider M, Kasivisvanathan V, Kirkham A, Klotz L, Ouzzane A, Padhani AR, Panebianco V, Pinto P, Puech P, Rannikko A, Renard-Penna R, Touijer K, Turkbey B, van Poppel H, Valdagni R, Walz J, Schoots I. Reporting Magnetic Resonance Imaging in Men on Active Surveillance for Prostate Cancer: The PRECISE Recommendations-A Report of a European School of Oncology Task Force. Eur Urol. 2017 Apr;71(4):648-655. doi: 10.1016/j.eururo.2016.06.011. Epub 2016 Jun 24. PMID: 27349615.
- Giganti F, Kasivisvanathan V, Allen C, Moore CM. The Importance of Being PRECISE in Prostate Magnetic Resonance Imaging and Active Surveillance. Eur Urol. 2021 Apr;79(4):560-563. doi: 10.1016/j.eururo.2021.01.016. Epub 2021 Feb 3. PMID: 33546915.
- Rajwa P, Pradere B, Quhal F, Mori K, Laukhtina E, Huebner NA, D'Andrea D, Krzywon A, Shim SR, Baltzer PA, Renard-Penna R, Leapman MS, Shariat SF, Ploussard G. Reliability of Serial Prostate Magnetic Resonance Imaging to Detect Prostate Cancer Progression During Active Surveillance: A Systematic Review and Meta-analysis. Eur Urol. 2021 May 18:S0302-2838(21)00325-0. doi: 10.1016/j.eururo.2021.05.001. Epub ahead of print. PMID: 34020828.