Neha Vapiwala1, J Karen Wong2, Elizabeth Handorf3, Jonathan Paly2, Amardeep Grewal1, Rahul Tendulkar4, Devon Godfrey5, David Carpenter5, Nancy P Mendenhall6, Randal H Henderson7, Bradley J Stish8, Carlos Vargas8, Joseph K Salama5, Brian J Davis8, Eric M Horwitz9. 1. Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania. 2. Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania. 3. Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, Pennsylvania. 4. Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, Ohio. 5. Department of Radiation Oncology, Duke University, Durham, North Carolina. 6. Department of Radiation Oncology, University of Florida, Gainesville, Florida. 7. Department of Radiation Oncology, UF Health Proton Therapy Institute, Jacksonville, Florida. 8. Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota. 9. Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Electronic address: Eric.Horwitz@fccc.edu.
Abstract
PURPOSE: Data comparing moderately hypofractionated intensity modulated radiation therapy (IMRT) and proton beam therapy (PBT) are lacking. We aim to compare late toxicity profiles of patients with early-stage prostate cancer treated with moderately hypofractionated PBT and IMRT. METHODS AND MATERIALS: This multi-institutional analysis included patients with low- or intermediate-risk biopsy-proven prostate adenocarcinoma from 7 tertiary referral centers treated from 1998 to 2018. All patients were treated with moderately hypofractionated radiation, defined as 250 to 300 cGy per daily fraction given for 4 to 6 weeks, and stratified by use of IMRT or PBT. Primary outcomes were late genitourinary (GU) and gastrointestinal (GI) toxicity. Adjusted toxicity rates were calculated using inverse probability of treatment weighting, accounting for race, National Comprehensive Cancer Network risk group, age, pretreatment International Prostate Symptom Score (GU only), and anticoagulant use (GI only). RESULTS: A total of 1850 patients were included: 1282 IMRT (median follow-up 80.0 months) and 568 PBT (median follow-up 43.9 months). Overall toxicity rates were low, with the majority of patients experiencing no late GU (56.6%, n = 1048) or late GI (74.4%, n = 1377) toxicity. No difference was seen in the rates of late toxicity between the groups, with late grade 3+ GU toxicity of 2.0% versus 3.9% (odds ratio [OR] 0.47; 95% confidence interval 0.17-1.28) and late grade 2+ GI toxicity of 14.6% versus 4.7% (OR 2.69; confidence interval 0.80-9.05) for the PBT and IMRT cohorts, respectively. On multivariable analysis, no factors were significantly predictive of GU toxicity, and only anticoagulant use was significantly predictive of GI toxicity (OR 1.90; P = .008). CONCLUSIONS: In this large, multi-institutional analysis of 1850 patients with early-stage prostate cancer, treatment with moderately hypofractionated IMRT and PBT resulted in low rates of toxicity. No difference was seen in late GI and GU toxicity between the modalities during long-term follow-up. Both treatments are safe and well tolerated.
PURPOSE: Data comparing moderately hypofractionated intensity modulated radiation therapy (IMRT) and proton beam therapy (PBT) are lacking. We aim to compare late toxicity profiles of patients with early-stage prostate cancer treated with moderately hypofractionated PBT and IMRT. METHODS AND MATERIALS: This multi-institutional analysis included patients with low- or intermediate-risk biopsy-proven prostate adenocarcinoma from 7 tertiary referral centers treated from 1998 to 2018. All patients were treated with moderately hypofractionated radiation, defined as 250 to 300 cGy per daily fraction given for 4 to 6 weeks, and stratified by use of IMRT or PBT. Primary outcomes were late genitourinary (GU) and gastrointestinal (GI) toxicity. Adjusted toxicity rates were calculated using inverse probability of treatment weighting, accounting for race, National Comprehensive Cancer Network risk group, age, pretreatment International Prostate Symptom Score (GU only), and anticoagulant use (GI only). RESULTS: A total of 1850 patients were included: 1282 IMRT (median follow-up 80.0 months) and 568 PBT (median follow-up 43.9 months). Overall toxicity rates were low, with the majority of patients experiencing no late GU (56.6%, n = 1048) or late GI (74.4%, n = 1377) toxicity. No difference was seen in the rates of late toxicity between the groups, with late grade 3+ GU toxicity of 2.0% versus 3.9% (odds ratio [OR] 0.47; 95% confidence interval 0.17-1.28) and late grade 2+ GI toxicity of 14.6% versus 4.7% (OR 2.69; confidence interval 0.80-9.05) for the PBT and IMRT cohorts, respectively. On multivariable analysis, no factors were significantly predictive of GU toxicity, and only anticoagulant use was significantly predictive of GI toxicity (OR 1.90; P = .008). CONCLUSIONS: In this large, multi-institutional analysis of 1850 patients with early-stage prostate cancer, treatment with moderately hypofractionated IMRT and PBT resulted in low rates of toxicity. No difference was seen in late GI and GU toxicity between the modalities during long-term follow-up. Both treatments are safe and well tolerated.
Authors: Noel E Donlon; Maria Davern; Fiona O'Connell; Andrew Sheppard; Aisling Heeran; Anshul Bhardwaj; Christine Butler; Ravi Narayanasamy; Claire Donohoe; James J Phelan; Niamh Lynam-Lennon; Margaret R Dunne; Stephen Maher; Jacintha O'Sullivan; John V Reynolds; Joanne Lysaght Journal: World J Gastroenterol Date: 2022-06-07 Impact factor: 5.374
Authors: Alicia Bao; Andrew R Barsky; Russell Maxwell; Justin E Bekelman; Stefan Both; John P Christodouleas; Curtiland Deville; Penny Fang; Zelig A Tochner; Neha Vapiwala Journal: Int J Part Ther Date: 2021-10-20