title: Time course of late rectal toxicity after radiation therapy for prostate cancer.
abstract: Rectum and bladder are the crucial organs at risk for curative radiation therapy of localized prostate cancer. We analyzed the incidence, profile and time course of late rectal radiation toxicity. A total of 320 patients with T1-3 prostate cancer were treated with three-dimensional conformal radiation therapy (3D-CRT). The prescription dose was 70 Gy for T1 and T2 patients (n=230) and 74 Gy for patients with locally advanced T3 tumors (n=90). Late rectal toxicity was graded according to the Fox Chase modification of the Radiation Therapy Oncology Group (RTOG) and Late Effects Normal Tissue Task Force (LENT) criteria. The median follow-up time was 6.2 years (range 0.2-10.7 years). At 5 years, the risk for the development of grade 2 and 3 rectal toxicities was 15.6 and 7.0%, respectively. All new cases of grade 2 and 3 rectal toxicities were observed within 5 years after treatment. Prevalence of grade 2 and 3 rectal symptoms showed fluctuation with maximum at 1.5 years and the minor peak at 4.5 years. Toxicity profile changed significantly over time. The proportion of rectal bleeding within grade 2 and 3 toxicity decreased from 85% at 1.5 years to 46% at 4.5 years. Conversely, the proportion of fecal incontinence among grade 2 and 3 rectal symptoms gradually increased (0% at 1.5 years vs 27% at 4.5 years). Late rectal radiation toxicity represents a dynamic process. Rectal bleeding decreases and fecal incontinence increases over time.
authors.affiliation: Department of Radiation Oncology, Multiscan and Pardubice Regional Hospital, Pardubice, Czech Republic. odrazka@seznam.cz
authors.forename: K
authors.initials: K
authors.lastname: Odrazka
authors.forename: M
authors.initials: M
authors.lastname: Dolezel
authors.forename: J
authors.initials: J
authors.lastname: Vanasek
authors.forename: M
authors.initials: M
authors.lastname: Vaculikova
authors.forename: M
authors.initials: M
authors.lastname: Zouhar
authors.forename: J
authors.initials: J
authors.lastname: Sefrova
authors.forename: P
authors.initials: P
authors.lastname: Paluska
authors.forename: M
authors.initials: M
authors.lastname: Vosmik
authors.forename: T
authors.initials: T
authors.lastname: Kohlova
authors.forename: I
authors.initials: I
authors.lastname: Kolarova
authors.forename: Z
authors.initials: Z
authors.lastname: Macingova
authors.forename: P
authors.initials: P
authors.lastname: Navratil
authors.forename: M
authors.initials: M
authors.lastname: Brodak
authors.forename: P
authors.initials: P
authors.lastname: Prosvic
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003967:Diarrhea / Q000453:epidemiology / Q000209:etiology; D005242:Fecal Incontinence / Q000453:epidemiology / Q000209:etiology; D006471:Gastrointestinal Hemorrhage / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011471:Prostatic Neoplasms / Q000532:radiotherapy* / Q000601:surgery; D020266:Radiotherapy, Conformal / Q000009:adverse effects*; D012007:Rectum / Q000528:radiation effects*; D013997:Time Factors