Inter-application displacement of brachytherapy dose received by the bladder and rectum of the patients with inoperable cervical cancer

Abstract

BackgroundThe aim of the study was to examine on the CT basis the inter-application displacement of the positions D0.1cc, D1cc and D2cc of the brachytherapy dose applied to the bladder and rectum of the patients with inoperable cervical cancer.Patients and methodsThis prospective study included 30 patients with cervical cancer who were treated by concomitant chemo-radiotherapy. HDR intracavitary brachytherapy was made by the applicators type Fletcher tandem and ovoids. For each brachytherapy application the position D0.1cc was determined of the bladder and rectum that receive a brachytherapty dose. Then, based on the X, Y, and Z axis displacement, inter-application mean X, Y, and Z axis displacements were calculated as well as their displacement vectors (R). It has been analyzed whether there is statistically significant difference in inter-application displacement of the position of the brachytherapy dose D0.1cc, D1cc and D2cc of the bladder and rectum. The ANOVA test and post-hoc analysis by Tukey method were used for testing statistical importance of differences among the groups analyzed. The difference among the groups analyzed was considered significant if p < 0.05.ResultsThere are significant inter-application displacements of the position of the brachytherapy dose D0,1cc, D1cc and D2cc of the bladder and rectum.ConclusionsWhen we calculate the cumulative brachytherapy dose by summing up D0,1cc, D1cc and D2cc of the organs at risk for all the applications, we must bear in mind their inter-application displacement, and the fact that it is less likely that the worst scenario would indeed happen.

Is 3D printing-gided three-dimensional brachytherapy suitable for cervical cancer: from one single research institute?

“…After the cervical cancer models were printed, radiotherapy doctors and patients conducted different aspects of validation for the models. The radiotherapy doctors participating in the study gave high recognition to the fidelity of the models, 3D printing adopted MRI image data, the resolution of MRI to cervical cancer tissue, and the surrounding tissue was significantly superior to that of CT images [19], the recon structed 3D model could reflect the actual situation of the tumor and was more valuable for guidance of radiotherapy, and the professionals' score of the overall evaluation of cer vical cancer model was 8.0 ± 0.8 points [20]. At the same time, the entity models from 3D printing turn the virtual reconstructionbased brachytherapy into direct planning on the entity models.…”

Interfraction dose variations in organs at risk during CT-based high-dose-rate brachytherapy in locally advanced carcinoma cervix: An early experience of a tertiary care Center

“…treated the patients with an EBRT dose of 45 Gy/25# along with concurrent chemotherapy with Cisplatin 40 mg/m 2 . [ 21 ] They interdigitated HDR brachytherapy applications from the second week of EBRT for a total five fractions of 7 Gy each. They found the average value of D 2cc (Gy) of the bladder the lowest for the second application (4.3 ± 1.4) and the highest for the fifth application (4.6 ± 1.3).…”