What's New With PI-RADS
The PI-RADS committee reaches out across borders to standardize prostate imaging across the globe.
The Bulletin sat down with Jeffrey C. Weinreb, MD, FACR, co-chair of the MR Prostate Imaging Reporting and Data System (PI-RADS) Steering Committee, to find out about the latest edition of PI-RADS and why international standardization is so important.
What's new in this version of PI-RADS?
The second version of the document, called PI-RADS v.2, features a lot of new information and an updated and more user friendly system for assessing findings on prostate MRI scans. For example, it provides a consensus definition of clinically significant prostate cancer and discusses such practical technical information as the advantages and disadvantages of using an endorectal coil and different magnetic field strengths the recommended strength for the magnetic field when performing multi-parametric MRI (mpMRI) and. The new version is consistent with other reporting tools developed by the ACR, such as BI-RADS and LI-RADS, in which findings are rated under categories 1–5, and the assessment categories are substantially simplified compared to the first version of PI-RADS. We have also added a set of appendices, including a lexicon developed under the direction of Katarzyna J. Macura, MD, PhD, FACR, that's consistent with terms used in RADLEX.
How was PI-RADS created?
AThe idea for PI-RADS came from meetings sponsored by the AdMEtech Foundation. The first version of PI-RADS, which aimed to standardize the diagnosis and reporting of prostate mpMRI, was developed by the European Society of Urogenital Radiology. That effort was chaired by Jelle Baerentz from the Netherlands, who also co-chaired the PI-RADSv2 Steering Committee with me. PI-RADS v.2 is the result of almost three years of collaboration between radiologists in Europe and North America along with consultation with an international group of pathologists, urologists, and others. After the initial publication of PI-RADS in 2012, we felt that it was important to make some important changes and additions based on our shared experiences and more recent scientific data.
Even though we had a team of prostate MRI experts who all knew what they were doing and were doing it well, , the manner in which each individual performed and interpreted the exam and then communicated the results varied widely. There was a lot of conferencing — sometimes at odd hours — to get everyone on the same page. We constantly challenged each other, and we learned a lot from one another about prostate cancer and MRI. Ultimately, everyone was willing to give some ground and change in order to gain consensus and achieve our goals.
Why is it important that imaging specialists use PI-RADS?
There is a growing body of published data that supports an important role for mpMRI for the diagnosis and management of prostate cancer. However, wide variations in the performance, interpretation, and reporting of prostate MRI exams has led to some inconsistensies and confusion, and it has emerged as an impediment to more widespread acceptance and use. As this modality expands, lack of standardization could lead to difficulties in comparing data, doing multi-institution trials, and providing meaningful results to doctors and patients. Furthermore, we want this document to go beyond radiology to all those who have a stake in a prostate cancer patient's welfare — not only radiologists, but urologists, radiation therapists, and pathologists. It allows us all to speak a common language.
What's in the future for PI-RADS?
PI-RADS is intended to be a living document — whenever there are changes in the field ready for clinical use, PI-RADS will reflect them. We're planning on including more information in the appendices, such as a reporting template and an online atlas of images able to demonstrate every imaginable finding you may see on the document.
Prostate MRI has also seen a lot of advances in the past few years. If the data proves a new development to be useful, we will include that information in PI-RADS. For example, we're watching the advance MRI imaging and contrast agents used to improve assessment of lymph node involvement with prostate cancer.
Where is PI-RADS found?
PI-RADS is free and available for anyone to use. You can access it at http://bit.ly/ACRPIRADS.