Sebastia Sabater1, Meritxell Arenas2, Roberto Berenguer3, Santiago Machin-Hamalainen4, Ignacio Andres3, Ma Mar Sevillano3, Esther Jimenez-Jimenez5, Ana Martos6, Veronica Lopez-Honrubia3, Jesus Fernandez-Lopez3. 1. Department of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Albacete, Spain. Electronic address: ssabaterm@gmail.com. 2. Department of Radiation Oncology, Hospital Universitari Sant Joan, Reus, Spain. 3. Department of Radiation Oncology, Complejo Hospitalario Universitario de Albacete (CHUA), Albacete, Spain. 4. C.S. General Ricardos, Area 11, Madrid, Spain. 5. Department of Radiation Oncology, Hospital Son Espases, Palma de Mallorca, Spain. 6. Department of Radiation Oncology, Hospital Central de Asturias, Oviedo, Spain.
Abstract
PURPOSE: Several studies have analyzed the effect of bladder filling during vaginal cuff brachytherapy (VCB), but the effect of rectum filling has not been studied. We sought to evaluate the effects of rectal volume on rectal doses during postoperative VCB. METHODS AND MATERIALS: Brachytherapy planning CT scans (334 sets) obtained from 92 consecutive patients treated with VCB were resegmented (bladder and rectum) and replanned retrospectively using the same parameters to homogenize data and improve analysis. Rectal volume and a set of values derived from dose-volume histograms (DVHs) were extracted (maximal dose [Dmax], D0.1cc, D1cc, and D2cc). Univariate and multivariate analyses were carried out to evaluate the association between rectal volume and DVH metrics after adjusting for other clinical factors. RESULTS: A positive significant correlation was observed between rectal volume correlated and Dmax, D0.1cc, D1cc, and D2cc. Multiple linear regression models found that rectal volume, cylinder angle position, and cylinder diameter variables correlated significantly with the different DVH parameters analyzed. These variables explained the 14.5% and 18% of variance on regression models. CONCLUSIONS: Larger rectal volumes are associated with higher rectal dose parameters during VCB fractions. Prospective studies are needed to investigate whether these data are linked to differences in rectal toxicity.
PURPOSE: Several studies have analyzed the effect of bladder filling during vaginal cuff brachytherapy (VCB), but the effect of rectum filling has not been studied. We sought to evaluate the effects of rectal volume on rectal doses during postoperative VCB. METHODS AND MATERIALS: Brachytherapy planning CT scans (334 sets) obtained from 92 consecutive patients treated with VCB were resegmented (bladder and rectum) and replanned retrospectively using the same parameters to homogenize data and improve analysis. Rectal volume and a set of values derived from dose-volume histograms (DVHs) were extracted (maximal dose [Dmax], D0.1cc, D1cc, and D2cc). Univariate and multivariate analyses were carried out to evaluate the association between rectal volume and DVH metrics after adjusting for other clinical factors. RESULTS: A positive significant correlation was observed between rectal volume correlated and Dmax, D0.1cc, D1cc, and D2cc. Multiple linear regression models found that rectal volume, cylinder angle position, and cylinder diameter variables correlated significantly with the different DVH parameters analyzed. These variables explained the 14.5% and 18% of variance on regression models. CONCLUSIONS: Larger rectal volumes are associated with higher rectal dose parameters during VCB fractions. Prospective studies are needed to investigate whether these data are linked to differences in rectal toxicity.
Authors: Katarzyna Sikorska; Agnieszka Zolciak-Siwinska; Adam Kowalczyk; Michał Bijok; Wojciech Michalski; Ewelina Gruszczynska Journal: J Contemp Brachytherapy Date: 2020-06-30
Authors: Matthew M Harkenrider; Alec M Block; Kaled M Alektiar; David K Gaffney; Ellen Jones; Ann Klopp; Akila N Viswanathan; William Small Journal: Brachytherapy Date: 2016-05-31 Impact factor: 2.362
Authors: Ingrid White; Dualta McQuaid; Helen McNair; Alex Dunlop; Steven Court; Naomi Hopkins; Karen Thomas; David Dearnaley; Shree Bhide; Susan Lalondrelle Journal: Phys Imaging Radiat Oncol Date: 2019-04-05