Main Session

Sep 28

PQA 02 - Lung Cancer/Thoracic Malignancies, Patient Reported Outcomes/QoL/Survivorship, Pediatric Cancer

2440 - Fifteen-Year Trends in Single-Fraction SBRT Utilization for Stage I Non-Small Cell Lung Cancer

04:45pm - 06:00pm PT

Hall F

Screen: 10

POSTER

Presenter(s)

Drew Moghanaki, MD, FASTRO, MPH - David Geffen School of Medicine at UCLA, Los Angeles, CA

D. Moghanaki¹, G. M. Videtic², A. K. Singh³, S. Siva⁴, D. L. Gage⁵, A. Lee¹, J. Deng¹, and M. Xiang¹; ¹Department of Radiation Oncology, University of California, Los Angeles, Los Angeles, CA, ²Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH, ³Department of Radiation Medicine, Roswell Park Comprehensive Cancer Center, Buffalo, NY, ⁴Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, VIC, Australia, ⁵VA Greater Los Angeles Healthcare System, Los Angeles, CA

Purpose/Objective(s): To evaluate utilization trends of stereotactic body radiation therapy (SBRT) prescribed as a single fraction (SF) for early-stage non-small cell lung cancer (NSCLC).

Materials/Methods: The National Cancer Database (NCDB) was queried to identify patients with stage I NSCLC treated with SBRT from 2006 to 2021 with either a SF or multi-fraction (MF) prescription. SF prescriptions ranging from 25-34 Gy, and MF prescriptions ranging from 10-20 Gy per fraction delivered in 3-5 fractions were considered concordant with National Comprehensive Cancer Network (NCCN) guidelines. Patients were excluded if they received chemotherapy or surgery. Annual utilization trends were analyzed using the Cochran-Armitage test. Factors predictive of treatment with SF were analyzed using a multivariable logistic regression model. Overall survival (OS) rates were compared using the log-rank test.

Results: A total of 83,377 patients were identified. SF was utilized in 937 patients (1.1%). The most frequent SF prescriptions were 34 Gy (39%), 27 Gy (28%), and 30 Gy (28%), while the most frequent MF prescriptions were 10 Gy × 5 (42%), 18 Gy × 3 (14%), and 12 Gy × 4 (14%). The proportion of facilities delivering SF significantly increased over time, from 0% in 2006 to 11% in 2021 (p<0.0001), with a greater increase observed at higher-volume centers and academic facilities. As of 2021, the proportion of facilities offering SF varied substantially based on annual lung SBRT case volume: 6% for centers treating <10 patients, 25% for centers treating 10-19 patients, 41% for centers treating 20-29 patients, and 69% for centers treating =30 patients per year. Despite the increased overall utilization, the proportion of lung SBRT treatments delivered as SF remained low, increasing from 0% to only 1.6% over the study period (p<0.0001). Factors associated with higher SF utilization included smaller tumor size (<2 cm), academic facility, higher-volume center, and later year of treatment (all p<0.0001). There was no statistically significant difference in unadjusted OS between SF and MF (p=0.89).

Conclusion: Although the use of SF SBRT for stage I NSCLC has been gradually increasing, particularly at high-volume academic centers, its overall utilization remains strikingly low. The lack of a significant survival difference between SF and MF SBRT, as seen in this study and two previous randomized phase II trials, suggests that SF is a non-inferior alternative to MF, while offering logistical and resource utilization advantages. Conversely, the most frequently prescribed MF regimen consisted of 5 fractions, despite the lack of prospective randomized data supporting this prescription for peripheral stage I NSCLC.