Variation in Abdominal Aortic Bifurcation Level among Pelvic Cancer Patients Undergoing Radiotherapy: A Retrospective CT-Based Analysis

Purpose: This retrospective study aimed to evaluate the impact of abdominal aortic bifurcation on radiation therapy planning for pelvic cancers, focusing on cervical cancer patients.

Background: Radiotherapy remains pivotal in the management of cervical cancer, ensuring precise delineation of target volumes is imperative to optimise treatment outcomes and minimise radiation-related toxicities.

Methods and Materials: Patients treated with radiotherapy for pelvic malignancies between 2022 and 2024 were included. CT scans with contrast were used for treatment planning, following standardised protocols. The level of abdominal aortic bifurcation relative to vertebral landmarks was analysed.

Results: Among 40 patients, bifurcation occurred predominantly at or above the L3–L4 intervertebral space (52.5%), anterior to L4 (25%), and at L4–L5 (22.5%).

Conclusion: Our findings underscore the necessity of CT-based planning to accurately target pelvic radiation fields. For facilities lacking CT capabilities, adjusting the upper border of radiation portals above L3–L4 is recommended for optimal cervical cancer treatment. The study underscores the importance of adopting computed tomography-based planning protocols whenever feasible, as they offer superior anatomical detail compared to conventional X-ray-based planning, ultimately enhancing treatment precision and efficacy.