Efficacy of Inspiratory Muscle Training on Respiratory Performance in Patients With Esophageal Cancer Receiving Combined Modality Therapy

Background and Purpose: Incidence rates of esophageal cancer remain high in Eastern Asia. In 2012, esophageal cancer was the 9th leading cause of cancer deaths in Taiwan. Whether surgical resection is possible, combined modality therapy is usually required for the treatment of esophageal cancer. In clinical observation, patients underwent combined modality therapy usually demonstrated respiratory muscle dysfunction which might further impair physical activity and quality of life. The purpose of this study is to investigate the effectiveness of inspiratory muscle training (IMT) on respiratory performance in patients with esophageal cancer during combined modality therapy.

Methods: This is a prospective interventional study design. A total of 45 patients with newly diagnosed esophageal cancer will be recruited from the Mackay Memorial Hospital. All tests will be performed at baseline (prior to cancer treatment), weekly during treatment, prior to surgery, and one month after surgery. Tests will include demographic data collection, respiratory muscle performance (maximal inspiratory and expiratory pressure tests combined with diaphragmatic surface electromyography, and pulmonary functional test), dyspnea, and the functional exercise test (6-min walk test). IMT will start with an intensity of 30% of maximal inspiratory pressure, 15 times/set, 3 sets/day, 7 days/week and training will continue until surgery is scheduled or 2 weeks after the completion of treatment if surgery is not suitable. Repeated measure ANOVA will be used for analyzing difference of parameters among various time points.

Clinical relevance: The results of this study will help to better understand the clinical beneficial effects (e.g., better functional capacity) of an added inspiratory muscle training during combined modality therapy in patients with esophageal cancer.