Setup Accuracy and Efficiency of Real-Time Video Assistance for Surface-Guided Positioning in Radiation Therapy of Right-Sided Locoregional Breast Cancer

Adv Radiat Oncol. 2025 Jun 9;10(9):101829. doi: 10.1016/j.adro.2025.101829. eCollection 2025 Sep.

Abstract

Purpose: Real-time video assistance in combination with surface guidance (SG) has been introduced in radiation therapy. In this study, we wanted to investigate the efficiency and accuracy of this new procedure for patients with right-sided locoregional breast cancer with special focus on the arm position.

Methods and materials: Twenty-six patients were included. Each patient was positioned using SG with real-time video assistance for half of the fractions. For the other half of the fractions, patient's surface was captured (including arm position) and visually compared to the reference surface before adjusting the patient position. This process was repeated until the patient position was acceptable. Pretreatment cone beam computer tomography (CBCT) was acquired at every fraction. Couch shifts after CBCT match were used to calculate systematic and random errors. CBCTs were also used to compare the actual treatment position of the nodal areas to the planned position. To analyze setup efficiency, 6 time points during the whole treatment procedure were recorded and analyzed.

Results: Our results showed negligible differences in setup accuracy when comparing couch shifts after CBCT match and the treated position of the nodal area. The group mean of the vertical couch shifts was significantly different between the 2 setup procedures (P = .03). The systematic error and the random error, however, were identical or almost identical. No other metrics regarding setup accuracy were significantly different. Setup efficiency was significantly improved using SG with real-time video assistance. By implementing real-time video assistance, setup time was reduced by an average of 40 seconds.

Conclusions: By implementing real-time video assistance in the setup of patients with right-sided locoregional breast cancer using SG, setup time can be significantly reduced without compromising setup accuracy.