Estimation of rectal fluctuations during radiotherapy of rectal cancer using CBCT measured on the bone structures and the posterior rectal wall

Salmič, Klemen (author), Oblak, Irena (author), Žager Marciuš, Valerija (author)

This study aims to determine the deviation of the rectum from the reference position in the various parts of the rectum. Fifty neoadjuvant patients were included in the retrospective study. All patients had long-course radiotherapy. At the time of treatment, we acquired six cone-beam computed tomography (CBCT) images. The anatomical structures of the rectum and sacrum were visualized on transverse CBCT images using Eclipse software. In the upper rectum, a statistically significant difference was found between the variable's posterior ± when aligned to bone structures (p = 0.017), while when aligned to the posterior rectal wall, the variables posterior ± represent a borderline statistical significance (p = 0.051). In the lower rectum, a statistically significant difference was found between the variables left ± (p = 0.0001) and between right ± (p = 0.008) when aligned to bone structures. When aligned to the posterior rectal wall, a statistically significant difference was found between left ± (p = 0.006) and right ± (p = 0.005). Daily CBCT imaging and adaptive radiotherapy should be considered, especially in patients with tumors in the highly mobile upper third of the rectum, to minimize these deviations and ensure optimal treatment accuracy.

• Language: English
• Keywords: rectal carcinoma, rectal movement, preoperative radiation, alignment method
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: ZF - Faculty of Health Sciences
• Publication status: Published
• Publication version: Version of Record
• Publication date: 01.01.2025
• Year: 2025
• Number of pages: Str. 57-64
• Numbering: Vol. 40, no. 1
• PID: 20.500.12556/RUL-170941
• UDC: 616-073:616-006
• ISSN on article: 1451-3994
• DOI: 10.2298/NTRP2501057S
• COBISS.SI-ID: 243408131
• Publication date in RUL: 22.07.2025

Record is a part of a journal

• Title: Nuclear Technology & Radiation Protection
• Shortened title: Nucl. Technol. Radiat. Prot.
• Publisher: Vinča Instituta of Nuclear Sciences
• ISSN: 1451-3994
• COBISS.SI-ID: 18296103

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Undetermined
• Keywords: karcinom rektuma, rektalno gibanje, predoperativno obsevanje, metoda poravnave