Preoperative expiratory muscle training for swallowing function in patients with esophageal cancer undergoing esophagectomy: A randomized controlled phase II trial protocol

Esophagectomy is a highly invasive and curative procedure for esophageal cancer. Although minimally invasive techniques reduce the incidence of pulmonary complications, postoperative dysphagia remains a common and clinically significant issue. Preoperative expiratory muscle training (EMT) may improve swallowing function by strengthening the relevant muscles; however, its effectiveness in patients with esophageal cancer has not been widely studied. This phase II randomized, controlled, double-blind trial has been designed to evaluate the effects of preoperative EMT on postoperative swallowing function in patients undergoing esophagectomy for thoracic esophageal squamous cell carcinoma. Forty patients will be randomly assigned (1:1) to either the EMT or sham-EMT group. EMT will be performed using the EX-1 Medic® device at 50-70% maximal expiratory pressure, whereas the control group will receive minimal resistance (10 cmH₂O). The primary outcome is the Penetration-Aspiration Scale score on the postoperative video-fluoroscopic swallowing study, targeted at postoperative days 10 (allowable window: postoperative days 6-14). The secondary outcomes will be assessed perioperatively (preoperative and/or postoperative, depending on the measure) and include tongue pressure, the Repetitive Saliva Swallowing Test, T he eating assessment test-10, respiratory muscle strength, appendicular skeletal muscle index, and exercise tolerance. This study has been registered at University Hospital Medical Information Network (UMINID:000057795). Recruitment began on June 10, 2025, is expected to continue until September 30, 2028. This trial will clarify whether preoperative EMT can improve swallowing function and reduce postoperative dysphagia in patients with esophageal cancer, potentially establishing a novel prehabilitation strategy in surgical care. Trial registration: UMIN Clinical Trials Registry (UMIN-CTR), UMIN000057795. Registered on May 8, 2025. https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000065994.