Interreader Variability of Prostate Imaging Reporting and Data System Version 2 in Detecting and Assessing Prostate Cancer Lesions at Prostate MRI

Leesburg, VA, May 27, 2019—The use of prostate multiparametric MRI (mpMRI) and targeted biopsy increases detection of clinically significant cancers while decreasing the diagnosis of indolent disease, according to a Focus On study published in the American Journal of Roentgenology

“One obstacle to broad application of prostate mpMRI is the lack of standardization and training necessary to interpret mpMR images,” wrote Matthew D. Greer, department of radiation oncology at the University of Washington School of Medicine in Seattle. 

To evaluate agreement among radiologists across experience levels in the detection and assessment of prostate cancer at mpMRI using Prostate Imaging Reporting and Data System version 2 (PI-RADSv2), Greer’s team evaluated a total study population of 163 patients. 

Of these, 110 underwent prostatectomy after MRI, and 53 evidenced normal MRI findings and transrectal ultrasound–guided biopsy results. 

Of the nine radiologists representing six countries and eight institutions who volunteered for the study, three had a high level of experience in prostate mpMRI (> 2000 cases in the last two years), three had a moderate level (500–2000 cases in the last two years), and three had a low level of experience (< 500 cases in the last two years). 

The authors’ results found that sensitivity for index lesions was comparable among all radiologists (average, 92.2%; p = 0.360), but specificity proved experience-dependent. 

Highly experienced readers had 84.0% specificity versus 55.2% for all others (p < 0.001), suggesting that the decision to perform biopsy be set at a lower threshold for novice prostate mpMRI radiologists and in centers where prostate MRI is an uncommon examination. 

As Radiology Business noted, “radiologists were blinded to prostate-specific antigen level and previous biopsy results, and providing such information could have improved results.”

Founded in 1900, the American Roentgen Ray Society (ARRS) is the first and oldest radiology society in the North America, dedicated to the advancement of medicine through the profession of radiology and its allied sciences. An international forum for progress since the discovery of the x-ray, ARRS maintains its mission of improving health through a community committed to advancing knowledge and skills with an annual scientific meeting, monthly publication of the peer-reviewed American Journal of Roentgenology (AJR), quarterly issues of InPractice magazine, topical symposia and AJR Live Webinars, print and online educational materials, as well as awarding scholarships via The Roentgen Fund®.