Hamid Raziee1, Fabio Y Moraes1, Jure Murgic1, Melvin L K Chua1, Melania Pintilie2, Peter Chung1, Cynthia Ménard3, Andrew Bayley1, Mary Gospodarowicz1, Padraig Warde1, Tim Craig1, Charles Catton1, Robert G Bristow1, David A Jaffray1, Alejandro Berlin4. 1. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Canada. 2. Department of Biostatistics, Princess Margaret Cancer Centre, University Health Network, Toronto, Canada. 3. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Canada; Département de radio-oncologie, Centre hospitalier de l'Université de Montréal (CHUM), Montréal, Canada. 4. Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Department of Radiation Oncology, University of Toronto, Canada. Electronic address: alejandro.berlin@rmp.uhn.ca.
Abstract
BACKGROUND AND PURPOSE: Dose-escalated radiotherapy (DE) improves outcomes in localized prostate cancer (PCa). The impact of DE in the context of image-guided radiotherapy (IGRT) remains unknown. Herein, we determined outcomes of three sequential cohorts treated with progressive DE-IGRT. MATERIALS AND METHODS: We analyzed data from 1998 to 2012. Patients treated with radical radiotherapy were included, with three sequential institutional schedules: (A) 75.6Gy, (B) 79.8Gy, (C) 78Gy, with 1.8, 1.9 and 2Gy/fraction, respectively. IGRT consisted of fiducial markers and daily EPID (A, B) or CBCT (C). RESULTS: 961 patients were included, with median follow-up of 6.1y. 30.5%, 32.6% and 36.9% were treated in A, B and C, respectively. Risk category distribution was 179 (18.6%) low-, 653 (67.9%) intermediate- and 129 (13.5%) high-risk. PSA, T-category, androgen deprivation use and risk distribution were similar among groups. BCR (biochemical recurrence) was different (p<0.001) between A, B and C with 5-year rates of 23%, 17% and 9%, respectively (HR 2.68 [95% CI 1.87-3.85] and 1.92 [95% CI 1.33-2.78] for A and B compared to C, respectively). Findings were most significant in the intermediate-risk category. Metastasis, cause-specific-death and toxicities were not different between cohorts. CONCLUSION: Our findings suggest continuous BCR improvement with progressive DE-IGRT. Prospective validation considering further DE with IGRT seems warranted.
BACKGROUND AND PURPOSE: Dose-escalated radiotherapy (DE) improves outcomes in localized prostate cancer (PCa). The impact of DE in the context of image-guided radiotherapy (IGRT) remains unknown. Herein, we determined outcomes of three sequential cohorts treated with progressive DE-IGRT. MATERIALS AND METHODS: We analyzed data from 1998 to 2012. Patients treated with radical radiotherapy were included, with three sequential institutional schedules: (A) 75.6Gy, (B) 79.8Gy, (C) 78Gy, with 1.8, 1.9 and 2Gy/fraction, respectively. IGRT consisted of fiducial markers and daily EPID (A, B) or CBCT (C). RESULTS: 961 patients were included, with median follow-up of 6.1y. 30.5%, 32.6% and 36.9% were treated in A, B and C, respectively. Risk category distribution was 179 (18.6%) low-, 653 (67.9%) intermediate- and 129 (13.5%) high-risk. PSA, T-category, androgen deprivation use and risk distribution were similar among groups. BCR (biochemical recurrence) was different (p<0.001) between A, B and C with 5-year rates of 23%, 17% and 9%, respectively (HR 2.68 [95% CI 1.87-3.85] and 1.92 [95% CI 1.33-2.78] for A and B compared to C, respectively). Findings were most significant in the intermediate-risk category. Metastasis, cause-specific-death and toxicities were not different between cohorts. CONCLUSION: Our findings suggest continuous BCR improvement with progressive DE-IGRT. Prospective validation considering further DE with IGRT seems warranted.
Authors: Antonio Lazo; Alejandro de la Torre-Luque; Gregorio Arregui; Daniel Rivas; Ana Serradilla; Joaquin Gómez; Francisca Jurado; María Isabel Núñez; Escarlata López Journal: Biology (Basel) Date: 2022-03-11