A Prospective Study on the Accuracy of Markerless Optical-Guided Self-Positioning In Breast Cancer Radiotherapy
Abstract
Purpose
[To investigate the clinical accuracy and feasibility of markerless optical-guided self-positioning for breast cancer patients undergoing radiotherapy.]
Methods
[This prospective study enrolled 10 breast cancer patients randomly divided into two groups. Five patients performed markerless optical-guided self-positioning and adjusted their own positioning based on the therapists' verbal instructions derived from optical deviation, while the other five were positioned by therapists based on skin marker points. After positioning, image-guided radiotherapy (IGRT) scans were acquired for all patients to measure residual setup errors (translational and rotational) and the real-time 2D transit dosimetry γ passing rates were analyzed intra-treatment.]
Results
[A total of 191 fractions were included in the statistical analysis. For the markerless optical-guided self-positioning group, residual IGRT offsets were -0.06±0.14 cm (lateral, LAT), -0.40±0.36 cm (longitudinal, LNG), 0.05±0.17 cm (vertical, VRT), 1.01±0.75° (Roll), and -0.37±0.74° (Pitch); For the marker-guided group, the offsets were 0.11±0.40 cm (LAT), -0.43±0.39 cm (LNG), -0.02±0.25 cm (VRT), 0.56±0.71° (Roll), and 1.10±1.10° (Pitch). The proportions of fractions with IGRT offsets <0.3 cm (LAT/LNG/VRT) were 95%/41%/93% (markerless optical-guided self-positioning group) vs. 56%/44%/72% (marker-guided group). The 2D transit dosimetry γ passing rates (3 mm/3%) were 95.83±5.25% for the optical-guided self-positioning group and 96.23±4.70% for the marker-guided group.]
Conclusion
[Markerless optical-guided self-positioning achieved comparable accuracy and 2D transit dosimetry γ passing rates to marker-guided setup, with superior reproducibility. Additionally, this mode not only eliminates the need for skin marking, thereby alleviating the physical and psychological burdens of breast cancer patients, but also offers the potential to reduce workflow labor intensity.]