Application of Surface-Guided Radiotherapy (SGRT) Combined with Cone-Beam CT (CBCT) In Lung Stereotactic Body Radiotherapy (SBRT)
Abstract
Purpose
To primarily evaluate setup accuracy and positioning stability of SGRT combined with CBCT in lung SBRT, with secondary assessments of target margin optimization, treatment safety, efficiency, and patient satisfaction.
Methods
A retrospective cohort included 24 lung cancer patients (14 males, 10 females; age 24–89 years, median 65 years) who underwent SGRT+CBCT-guided SBRT (2020–2025). The cohort comprised 19 single-lung-target and 5 multi-target (2–3 lesions) patients, totaling 120 fractions. All received 3000–5000 cGy/5 fractions with Wingboard + knee pad immobilization. The workflow included 4DCT-based target delineation, a 3 mm internal target volume (ITV) margin for peripheral lesions, SGRT initial positioning, CBCT verification and correction, and continuous SGRT monitoring during treatment (20–25 Hz). SPSS 26.0 was used for analyses (descriptive statistics, independent samples t-tests, and Wilcoxon tests; P value 0.05). This stability boosted efficiency, with treatment durations of 10–15 min (single-target) and 14–18 min (multi-target). All 24 patients tolerated daily irradiation without interruption, characterized by stable hematology, no grade ≥2 CTCAE adverse events, and 33.3% with self-resolving grade 1 fatigue. Dosimetrically, PTV D95 remained 97.8–98.2% for adequate coverage. Patient outcomes were favorable: 100% satisfaction and a mean Visual Analog Scale (VAS) comfort score of 8.5±1.2.
Conclusion
SGRT combined with CBCT ensures superior setup accuracy and progressively improving positioning stability with repeated sessions in lung SBRT, driving higher treatment efficiency alongside good irradiation tolerance, favorable target margin optimization, safety, and patient acceptance across subgroups, meriting widespread clinical implementation.