Real-Time Image Guided Ablative Prostate Cancer Radiation Therapy: Results From the TROG 15.01 SPARK Trial

• DOI: 10.1016/j.ijrobp.2020.03.014
• Publication Date: 2020-03-29T13:55:33Z
• Authors: Paul Keall; Doan Trang Nguyen; Ricky O'Brien; Emily Hewson; Helen Ball; Per Poulsen; Jeremy Booth; Peter Greer; Perry Hunter; Lee Wilton; Regina Bromley; John Kipritidis; Thomas Eade; Andrew Kneebone; George Hruby; Trevor Moodie; Amy Hayden; Sandra Turner; Sankar Arumugam; Mark Sidhom; Nicholas Hardcastle; Shankar Siva; Keen-Hun Tai; Val Gebski; Jarad Martin
• Keywords: Ablation Techniques; Male; image-guided radiation therapy; Time Factors; 0299 Other Physical Sciences; Sustainable Development Goals; 610; Prostatic Neoplasms; Middle Aged; prostate cancer; radiation therapy; 3. Good health; 03 medical and health sciences; Treatment Outcome; 0302 clinical medicine; male; XXXXXX - Unknown; 616; middle aged; Humans; Radiotherapy, Intensity-Modulated; SDG 3

Kilovoltage intrafraction monitoring (KIM) is a novel software platform implemented on standard radiation therapy systems and enabling real-time image guided radiation therapy (IGRT). In a multi-institutional prospective trial, we investigated whether real-time IGRT improved the accuracy of the dose patients with prostate cancer received during radiation therapy.Forty-eight patients with prostate cancer were treated with KIM-guided SABR with 36.25 Gy in 5 fractions. During KIM-guided treatment, the prostate motion was corrected for by either beam gating with couch shifts or multileaf collimator tracking. A dose reconstruction method was used to evaluate the dose delivered to the target and organs at risk with and without real-time IGRT. Primary outcome was the effect of real-time IGRT on dose distributions. Secondary outcomes included patient-reported outcomes and toxicity.Motion correction occurred in ≥1 treatment for 88% of patients (42 of 48) and 51% of treatments (121 of 235). With real-time IGRT, no treatments had prostate clinical target volume (CTV) D98% dose 5% less than planned. Without real-time IGRT, 13 treatments (5.5%) had prostate CTV D98% doses 5% less than planned. The prostate CTV D98% dose with real-time IGRT was closer to the plan by an average of 1.0% (range, -2.8% to 20.3%). Patient outcomes showed no change in the 12-month patient-reported outcomes compared with baseline and no grade ≥3 genitourinary or gastrointestinal toxicities.Real-time IGRT is clinically effective for prostate cancer SABR.