1746 IMPACT OF ROBOTIC IMRT ON NORMAL TISSUE SPARING IN THE TREATMENT OF PROSTATE CANCER AS COMPARED TO CONVENTIONAL IMRT

You have accessJournal of UrologyProstate Cancer: Localized VII1 Apr 20101746 IMPACT OF ROBOTIC IMRT ON NORMAL TISSUE SPARING IN THE TREATMENT OF PROSTATE CANCER AS COMPARED TO CONVENTIONAL IMRT Omar Dawood, Colin Sims, John Dooley, Paul Meskell, Alan Katz, and Calvin Maurer Omar DawoodOmar Dawood Sunnyvale, CA More articles by this author , Colin SimsColin Sims Sunnyvale, CA More articles by this author , John DooleyJohn Dooley Sunnyvale, CA More articles by this author , Paul MeskellPaul Meskell Sunnyvale, CA More articles by this author , Alan KatzAlan Katz Mineola, NY More articles by this author , and Calvin MaurerCalvin Maurer Sunnyvale, CA More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2010.02.1595AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Conventional IMRT treatment of prostate cancer has evolved over the past decade but still is limited by a lack of control for prostate motion. Instead, large margins surrounding the prostate are used, impacting abilities to spare the bladder, rectum and neurovascular bundles. Robotic IMRT, as enabled by the CyberKnife VSI System, addresses this issue by tracking and correcting for prostate motion throughout treatment. We compared conventional IMRT versus Robotic IMRT treatments of low and intermediate risk prostate cancer. METHODS CT datasets from patients with organ confined, low and intermediate risk prostate cancer were used to develop IMRT treatment plans on both the CyberKnife VSI System and the Varian Rapid Arc System. The target as well as critical structures were identically contoured for both systems, and clinical margin expansions were made in line with current clinical practice for each IMRT device. Overall planning target volume (PTV) and doses to the rectum and bladder were compared. RESULTS Both Robotic IMRT and conventional IMRT were able to ensure 95% coverage of the PTV for low and intermediate risk patients. The mean PTV for the Robotic IMRT cases was 35% smaller than that of the conventional IMRT cases, owing to the smaller clinical margin expansion made possible by tracking and continual intrafraction correction for prostate motion during treatment. Analysis of dose to critical structures found that the volume of rectum receiving 90% of the prescription dose (V90) was 53% higher and the bladder V90 was 64% higher for conventional IMRT as compared to Robotic IMRT (Fig 1). CONCLUSIONS Robotic IMRT enables clinicians to deliver treatment for low and intermediate risk prostate cancer with increased precision and accuracy as compared to conventional IMRT, resulting in smaller overall target volumes and reductions of dose to surrounding critical structures. These differences may result in reduced post treatment morbidity. Further clinical studies and follow-up will be required to assess this effect. © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 183Issue 4SApril 2010Page: e674-e675 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.MetricsAuthor Information Omar Dawood Sunnyvale, CA More articles by this author Colin Sims Sunnyvale, CA More articles by this author John Dooley Sunnyvale, CA More articles by this author Paul Meskell Sunnyvale, CA More articles by this author Alan Katz Mineola, NY More articles by this author Calvin Maurer Sunnyvale, CA More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...