2428 - A Pilot Study to Evaluate Percussive Ventilation Breath Hold to Improve Lung Stereotactic Ablative Radiotherapy (PVB-SABR)
Presenter(s)
W. X. Mai1, K. Z. Huang1, S. Wong1, A. Yauger1, J. Langer1, D. Free2, P. Gebeyehu2, A. Swamy1, K. Z. Flores3, A. Kathiravan1, S. Merrill2, D. Sianez-Torres2, A. Kokinos2, L. Skinner3, E. Blomain4, and B. W. Loo Jr5; 1Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, 2Department of Interventional Pulmonology, Stanford University, Stanford, CA, 3Department of Radiation Oncology, Stanford University, Palo Alto, CA, 4Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, 5Stanford University School of Medicine, Stanford, CA
Purpose/Objective(s): Stereotactic ablative radiotherapy (SABR) effectively treats early-stage lung cancer and metastasis, but tumor motion poses accuracy challenges. Inspiratory breath hold is an established strategy to mitigate lung motion, but its practicality is limited, especially in patients with reduced lung capacity. Percussive ventilation breath hold (PVB) is an innovative, non-invasive respiratory technique designed to maintain breathing function with minimal chest motion, thus eliminating motion uncertainty and improving treatment safety. This pilot study marks the first attempt to apply PVB to lung SABR treatments. The primary objectives include determining tolerance of PVB in healthy volunteers (Arm 1) and evaluating the success rate of PVB-SABR in lung cancer patients (Arm 2). Secondary objectives involve examining time-related endpoints for breath hold duration and assessing dosimetric benefits.
Materials/Methods: This analysis includes 15 healthy volunteers and 5 patients enrolled between 1/2023 - 2/2025. Any person age 18 or older who would be deemed clinically eligible to undergo lung SABR treatment qualified to participate. Patients in Arm 2 require a diagnosis of primary lung cancer or lung metastasis. PVB is administered with Percussionaire IPV-2C or Monsoon III. Participants either underwent mock simulation with PVB (Arm 1) or PVB-SABR treatment (Arm 2). CO2 levels were monitored transcutaneously (Sentec), and adverse effects were recorded according to CTCAE v5.
Results: In Arm 1, 14 of 15 volunteers (93%) tolerated PVB for 5 minutes. 7 of 15 (47%) successfully maintained a 10-minute breath hold. When comparing devices, the Monsoon device resulted in 4 of 5 patients (90%) achieving a 10-minute breath hold, compared to 3 of 10 patients (30%) on the IPV-2C device. CO2 levels increased by an average of 8.18 mmHg on IPV-2C compared to 0.6 mmHg on the Monsoon (p=0.002). Of the 5 patients currently enrolled in Arm 2, 4 (80%) were successfully treated with PVB-SABR. One patient declined to continue due to discomfort with PVB during initial evaluation. 3 of the 4 (75%) PVB-SABR treated patients maintained a 10-minute breath hold, while one stopped shortly after 8 minutes. All treated patients sustained a single breath hold from beginning of CBCT verification to treatment completion (average 8.2 minutes). Minimal adverse events were documented, with dry mouth being the most notable (40% in healthy volunteers and 100% in treated patients). All adverse events resolved within 24 hours. Lastly, subjects demonstrated the ability to repeat multiple, sequential breath holds using the PVB technique.
Conclusion: This is the first trial evaluating PVB-SABR for lung cancer treatment, demonstrating high tolerance with minimal adverse effects. The Monsoon III appears superior in patient tolerance and gas exchange. These findings highlight PVB’s potential as a safe, effective motion management strategy for lung SABR. Future dosimetric analysis may reveal target-sparing benefits. IRB 63842.