Urological surgeons to debate value of endorectal MRI
There is no consensus about the role of magnetic resonance imaging (MRI) in prostate cancer, and the reported accuracy of prostate cancer detection with MRI varies widely.
During today’s Point-Counterpoint debate, Endorectal MRI for the Preoperative Staging of Prostate Cancer, two of the world’s leading urological surgeons will deliberate the contribution of MRI to staging nomograms. The 20-minute presentation begins at 11:40 a.m. and concludes the morning Plenary Session in Hall D at the Walter E. Washington Convention Center.
“The role of MRI in surgical planning is controversial,” said session moderator James A. Eastham, M.D., Chief of Urology Service in the Department of Surgery at the Memorial Sloan-Kettering Cancer Center in New York City.
While MRI may allow for more accurate local cancer staging, one study reported that endorectal MRI accurately predicts pathological T3 disease (extraprostatic extension, EPE) and seminal vesicle invasion (SVI) with a positive and negative predictive value of only 50 percent and 61 percent, respectively.
In another study of 176 prostate cancer patients, preoperative 1.5 T MRI findings were compared with the final histology of the radical prostatectomy specimen. MRI correctly identified EPE in 66 percent of men, and the sensitivity and specificity were 69 percent and 90 percent, respectively, for per patient MRI identification of EPE.
“These studies suggest that MRI may not be sensitive enough to predict small areas of EPE and thus not useful for surgical planning,” Dr. Eastham said. “In contrast to these studies, other investigators have concluded that the contribution of MRI tostaging nomograms was significant in all risk categories, but the greatest benefit was seen in the intermediate and high risk groups.”
Ashutosh K. Tewari, M.D., a board certified American urologist, oncologist and clinical researcher at Weill Cornell Medical College of Cornell University in New York City, where he directs the Institute of Prostate Cancer and Robotic Surgery, will debate as a proponent of endorectal MRI. Dr. Tewari is recognized as a world-renowned expert on urological oncology with more than 250 peer reviewed articles to his credit.
Joseph A. Smith, Jr., M.D., the William L. Bray Professor and Chairman of the Department of Urologic Surgery at Vanderbilt University Medical Center in Nashville, Tennessee, will argue against the approach. Along with his research in benign prostatic hyperplasia, Dr. Smith’s primary interest has been in the surgical and multidisciplinary management of urological cancers.
“Both are well known, thoughtful, highly experienced prostate cancer surgeons,” Dr. Eastham said. “Dr. Ash Tewari will argue that MRI significantly improves the ability of the surgeon to perform radical prostatectomy, whereas Dr. Joseph Smith will support the concept that MRI is not beneficial in surgical planning.”
The continuous evolution of MRI through improved technology as well as a better understanding of the imaging criteria associated with prostate cancer and the inevitable “learning curve” of the interpreting radiologists may be reasons for the conflicting reports.
At present, according to the American College of Radiology’s appropriateness criteria, endorectal MRI may be considered in patients with high range prostate specific antigen and high volume disease on biopsy.
“Admittedly, if MRI could detect every prostate cancer, the technology would benefit all patients with the disease,” Dr. Eastham said. “However, no matter how experienced the reader is, MRI does not reach this level of accuracy. Despite this, one might argue that when a study is normal or near normal, MRI can help to characterize a cancer indirectly.”