Benefits of Continuous Positive Airway Pressure (CPAP) in Radiotherapy: A Prospective Trial

Abstract Purpose This study aimed to study the impact of continuous positive airway pressure (CPAP) on chest anatomy and tumor motion in patients receiving radiation therapy. Methods and Materials Patients with primary or secondary lung tumors, left-sided breast cancer, or liver metastases referred for radiation therapy were trained to breathe with a CPAP device using a face mask to a maximal pressure of 15 cm H2O. Three- and 4-dimensional computed tomography simulation was performed twice for each patient: once with free breathing (FB) and again using CPAP. Volumetric and dosimetric parameters of treatment plans were compared. Results Forty-nine patients were enrolled, of whom 6 withdrew consent before simulation and 3 withdrew because of discomfort. Thus, a total of 40 patients were analyzed. Twenty-seven patients (67.5%) were treated with CPAP based on confirmation of the volumetric or dosimetric benefit of CPAP. Mean lung volume increased by 37% (P Conclusions In this prospective trial, the use of CPAP was associated with significant volumetric and dosimetric benefits compared with FB. CPAP was safe, simple to implement, and well tolerated by most patients, and it should be studied further as a method to reduce the risk of lung and heart toxicity.