title: Outcomes in men with large prostates (≥ 60 cm(3)) treated with definitive proton therapy for prostate cancer.
abstract: Large prostate size is associated with higher rates of genitourinary and gastrointestinal toxicities after definitive treatment for prostate cancer, and because of this many men will undergo cytoreduction with androgen deprivation therapy (ADT) before definitive therapy, which results in its own unique toxicities and worsens quality of life. This series investigates genitourinary and gastrointestinal toxicity in men with large prostates (> 60 cm(3)) undergoing definitive proton therapy (PT) for prostate cancer. Material and methods. From 2006 to 2010, 186 men with prostates ≥ 60 cm(3) were treated with definitive PT (median dose, 78 CGE) for low- (47%), intermediate- (37%) and high-risk (16%) prostate cancer. Median prostate size was 76 cm(3) (range, 60-143 cm(3)) and pretreatment IPSS was > 15 in 27%. At baseline, 51% were managed for obstructive symptoms with transurethral resection of the prostate (TURP) (9.7%) or medical management with α blockers (32%), 5 α-reductase inhibitors (15%), and/or saw palmetto (11%). Fourteen men received ADT for cytoreduction. Results. Median follow-up was two years. Grade 3 genitourinary toxicities occurred in 14 men, including temporary catheterization (n = 7), TURP (n = 6), and balloon dilation for urethral stricture (n = 1). Multivariate analysis demonstrated pretreatment medical management (p = 0.0065) and pretreatment TURP (p = 0.0002) were significantly associated with grade 3 genitourinary toxicity. One man experienced grade 3 gastrointestinal toxicity and 15 men had grade 2 gastrointestinal toxicities. On multivariate analysis, dose > 78 CGE was associated with increased grade 2 + gastrointestinal toxicity (p = 0.0142). Conclusion. Definitive management of men with large prostates without ADT was associated with low rates of genitourinary and gastrointestinal toxicity.
authors.affiliation: Department of Radiation Oncology, University of Florida College of Medicine, Gainesville, Florida 32206, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: McGee
authors.forename: Nancy P
authors.initials: NP
authors.lastname: Mendenhall
authors.forename: Randal H
authors.initials: RH
authors.lastname: Henderson
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Morris
authors.forename: Romaine C
authors.initials: RC
authors.lastname: Nichols
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Marcus
authors.forename: Zuofeng
authors.initials: Z
authors.lastname: Li
authors.forename: William M
authors.initials: WM
authors.lastname: Mendenhall
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Williams
authors.forename: Bradford S
authors.initials: BS
authors.lastname: Hoppe
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology* / Q000532:radiotherapy*; D000368:Aged; D000369:Aged, 80 and over; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D052801:Male Urogenital Diseases / Q000453:epidemiology / Q000209:etiology; D008875:Middle Aged; D009929:Organ Size / Q000502:physiology; D011379:Prognosis; D011467:Prostate / Q000473:pathology* / Q000502:physiology; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000532:radiotherapy*; D061766:Proton Therapy / Q000009:adverse effects; D011832:Radiation Injuries / Q000453:epidemiology; D011880:Radiotherapy Planning, Computer-Assisted; D012189:Retrospective Studies; D016896:Treatment Outcome; D047368:Tumor Burden; D014566:Urogenital System / Q000503:physiopathology / Q000528:radiation effects