Abstract
BackgroundThe study aims to determine possible dose-volume response relationships between the rectum, sigmoid colon and small intestine and the ‘excessive mucus discharge’ syndrome after pelvic radiotherapy for gynaecological cancer.Methods and materialsFrom a larger cohort, 98 gynaecological cancer survivors were included in this study. These survivors, who were followed for 2 to 14 years, received external beam radiation therapy but not brachytherapy and not did not have stoma. Thirteen of the 98 developed excessive mucus discharge syndrome. Three self-assessed symptoms were weighted together to produce a score interpreted as ‘excessive mucus discharge’ syndrome based on the factor loadings from factor analysis. The dose-volume histograms (DVHs) for rectum, sigmoid colon, small intestine for each survivor were exported from the treatment planning systems. The dose-volume response relationships for excessive mucus discharge and each organ at risk were estimated by fitting the data to the Probit, RS, LKB and gEUD models.ResultsThe small intestine was found to have steep dose-response curves, having estimated dose-response parameters: γ50: 1.28, 1.23, 1.32, D50: 61.6, 63.1, 60.2 for Probit, RS and LKB respectively. The sigmoid colon (AUC: 0.68) and the small intestine (AUC: 0.65) had the highest AUC values. For the small intestine, the DVHs for survivors with and without excessive mucus discharge were well separated for low to intermediate doses; this was not true for the sigmoid colon. Based on all results, we interpret the results for the small intestine to reflect a relevant link.ConclusionAn association was found between the mean dose to the small intestine and the occurrence of ‘excessive mucus discharge’. When trying to reduce and even eliminate the incidence of ‘excessive mucus discharge’, it would be useful and important to separately delineate the small intestine and implement the dose-response estimations reported in the study.
Highlights
Few, if any, survivors who have undergone radiotherapy for a pelvic tumor return to the intestinal health they had before treatment
We interpret the results for the small intestine to reflect a relevant link
An association was found between the mean dose to the small intestine and the occurrence of ‘excessive mucus discharge’
Summary
If any, survivors who have undergone radiotherapy for a pelvic tumor return to the intestinal health they had before treatment. Pelvic-radiation disease contracted during radiotherapy may consist of as many as 30 different late adverse intestinal effects [1] that compromise the survivor’s daily life. One such late adverse effect is excessive mucus discharge or ‘mucus syndrome’, which is a patient-reported outcome. We do not know the extent to which ionizing radiation delivered to the small intestine, sigmoid colon, or rectum may be responsible for inducing this specific late adverse effect. The study aims to determine possible dose-volume response relationships between the rectum, sigmoid colon and small intestine and the ‘excessive mucus discharge’ syndrome after pelvic radiotherapy for gynaecological cancer
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call