SU-E-T-579: Dosimetric Benefits of Online Adaptive Replanning for Post-Operative Radiation Therapy of Prostate Bed

Medical Physics
Feng LiuX Allen Li

Abstract

To demonstrate the dosimetric benefits of using an online adaptive replanning scheme to address interfractional variations in radiotherapy of prostate bed. We have previously developed an online adaptive replanning tool (RealART, Prowess Inc.) aiming to address interfractional variations including organ deformation and rotation. Using this tool, we analyzed a total of 102 daily pre-treatment CTs acquired using an in-room CT (CTVision, Siemens) for 10 patients treated with post-operative IMRT of prostate bed. The PTV was assumed to be the volume enclosed by the 95% prescription isodose surface generated for the conventional four field box. On each daily CT set, contours of the PTV, rectum and bladder were generated by populating the planning contours using an auto-segmentation tool based on deformable registration (ABAS, Elekta) with manual editing. Four plans were generated and compared: (1) IGRT (repositioning) plan by copying the original plan with aligning the anterior rectal wall from the daily CT to that of the planning CT, (2) IGRT plan by copying the original plan with aligning the surgical clips, (3) online adaptive plan by tailoring the original plan to conform to the anatomy of the day, and (4) a new plan re- optimize...Continue Reading

Related Concepts

Related Feeds

Bladder Carcinoma In Situ

Bladder Carcinoma In Situ is a superficial bladder cancer that occurs on the surface layer of the bladder. Discover the latest research on this precancerous condition in this feed.

Related Papers

Veterinary Radiology & Ultrasound : the Official Journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association
Jessica R NiesetSusan M Larue
Radiotherapy and Oncology : Journal of the European Society for Therapeutic Radiology and Oncology
X Allen LiBeth Erickson
© 2022 Meta ULC. All rights reserved