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 ¼ 230) and 74 Gy for patients with locally advanced T3 tumors (n ¼ 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.

Defecation into clothing without forewarning and mean radiation dose to bowel and anal-sphincter among gynecological cancer survivors

“…Normal tissue injury induced by ionizing radiation is thought to be a progressive process. However, there are reports showing both an increase and a decrease of rectal symptoms in prostate cancer survivors with time [23]. In the present study we did not find any statistically significant increase in risk for developing defecation into clothing without forewarning during follow-up from 2 to 14 years after pelvic radiation therapy.…”

Anal sphincter dysfunction in patients treated with primary radiotherapy for anal cancer: a study with the functional lumen imaging probe

“…We recruited AC patients who had finished their RT or CRT more than 18 months previously. As late anorectal toxicity may represent a dynamic process [47], it could be interesting to repeat the study in 2-3years to reveal development over time. There is a possibility that patients with symptoms are more willing to participate in this type of study, causing us to overestimate the differences between AC patients and healthy volunteers by selection bias.…”

Prospective evaluation of quality of life 54 months after high-dose intensity-modulated radiotherapy for localized prostate cancer

“…Studies tend to be retrospective [17]. Long-term QoL after IMRT has received attention in a limited number of prospective studies [18,19] even though adverse effects are known to occur late (over 30 months) [20,21]. …”