Yasir Alayed1, Patrick Cheung2, William Chu2, Hans Chung2, Melanie Davidson2, Ananth Ravi2, Joelle Helou3, Liying Zhang4, Alexandre Mamedov4, Angela Commisso4, Kristina Commisso5, Andrew Loblaw6. 1. Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Radiation Oncology, University of Toronto, Canada; Division of Radiation Oncology, College of Medicine, King Saud University, Riyadh, Saudi Arabia. 2. Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Radiation Oncology, University of Toronto, Canada. 3. Department of Radiation Oncology, University of Toronto, Princess Margaret Cancer Centre, Canada. 4. Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Canada. 5. University Health Network, Toronto, Canada. 6. Odette Cancer Centre, Sunnybrook Health Sciences Centre, Toronto, Canada; Department of Radiation Oncology, University of Toronto, Canada; Department of Health Policy, Measurement and Evaluation, University of Toronto, Canada. Electronic address: andrew.loblaw@sunnybrook.ca.
Abstract
PURPOSE: Ultrahypofractionation is appealing for prostate cancer (PCa) due to low α/β, and increasing the dose per fraction could improve the therapeutic index. Here we report the outcomes of a phase II prostate SABR trial using two fractions. METHODS: Patients had low or intermediate risk prostate cancer. Three gold fiducials were implanted for image guidance. The clinical target volume (CTV) included the prostate only, and the planning target volume (PTV) was a 3 mm expansion enabled through the use of a rectal immobilization device. The dose prescribed was 26 Gy in 2 weekly fractions (EQD2 110 Gy1.4). The primary endpoint was quality of life using EPIC, and minimal clinically important change (MCIC) was defined as an EPIC QOL decrease >0.5 SD. RESULTS: 30 patients were accrued with a median follow-up of 49.3 months. 10% had low-risk, 33% had favourable intermediate-risk and 57% had unfavourable intermediate-risk PCa. Five patients received a short course of ADT. Median nPSA was 0.2 ng/ml. One patient had BF and is being observed. 56.6% of patients had a 4yPSARR. Six (20.7%) patients had a MCIC in the urinary domain, 6 (21.4%) had a MCIC in the bowel domain, and 3 (20%) had a MCIC in the sexual domain. CONCLUSIONS: Two-fraction SABR in prostate cancer is safe and feasible, with a minimal change in QOL and a low rate of late grade 3-4 toxicity. The PSA kinetics and biochemical control rates are encouraging given that the majority had unfavourable intermediate-risk disease, although longer follow-up is required.
PURPOSE: Ultrahypofractionation is appealing for prostate cancer (PCa) due to low α/β, and increasing the dose per fraction could improve the therapeutic index. Here we report the outcomes of a phase II prostate SABR trial using two fractions. METHODS:Patients had low or intermediate risk prostate cancer. Three gold fiducials were implanted for image guidance. The clinical target volume (CTV) included the prostate only, and the planning target volume (PTV) was a 3 mm expansion enabled through the use of a rectal immobilization device. The dose prescribed was 26 Gy in 2 weekly fractions (EQD2 110 Gy1.4). The primary endpoint was quality of life using EPIC, and minimal clinically important change (MCIC) was defined as an EPIC QOL decrease >0.5 SD. RESULTS: 30 patients were accrued with a median follow-up of 49.3 months. 10% had low-risk, 33% had favourable intermediate-risk and 57% had unfavourable intermediate-risk PCa. Five patients received a short course of ADT. Median nPSA was 0.2 ng/ml. One patient had BF and is being observed. 56.6% of patients had a 4yPSARR. Six (20.7%) patients had a MCIC in the urinary domain, 6 (21.4%) had a MCIC in the bowel domain, and 3 (20%) had a MCIC in the sexual domain. CONCLUSIONS: Two-fraction SABR in prostate cancer is safe and feasible, with a minimal change in QOL and a low rate of late grade 3-4 toxicity. The PSA kinetics and biochemical control rates are encouraging given that the majority had unfavourable intermediate-risk disease, although longer follow-up is required.
Authors: Eric Leung; Adam P Gladwish; Melanie Davidson; Amandeep Taggar; Vikram Velker; Elizabeth Barnes; Lucas Mendez; Elysia Donovan; Lilian T Gien; Allan Covens; Danielle Vicus; Rachel Kupets; Helen MacKay; Kathy Han; Patrick Cheung; Liying Zhang; Andrew Loblaw; David P D'Souza Journal: JAMA Oncol Date: 2022-06-01 Impact factor: 33.006
Authors: David J Byun; Daniel J Gorovets; Lauren M Jacobs; Laura Happersett; Pengpeng Zhang; Xin Pei; Sarah Burleson; Zhigang Zhang; Margie Hunt; Sean McBride; Marisa A Kollmeier; Michael J Zelefsky Journal: Radiat Oncol Date: 2020-10-16 Impact factor: 3.481
Authors: J Schaule; M Chamberlain; L Wilke; M Baumgartl; J Krayenbühl; M Zamburlini; M Mayinger; N Andratschke; S Tanadini-Lang; M Guckenberger Journal: Radiat Oncol Date: 2021-09-26 Impact factor: 3.481