Principles and experience with cone-beam CT based online adaptive therapy

There is growing clinical evidence supporting adaptive radiotherapy (ART) to reduce the dose to healthy tissues and ensure more accurate delivery of dose to tumors for cancer patients. Technological advancements have made online ART a reality: fast, high-quality imaging combined with artificial intelligence (AI)-assisted auto-contouring and automated planning make it possible to re-optimize a treatment plan for today's anatomy in just a few minutes. In this talk, I will discuss the clinical benefits and challenges of online adaptive therapy. I will also review my institution's first year of experience with the Varian Ethos, a system designed to use cone-beam CT imaging for online ART.