Impact of preoperative exercise therapy on surgical outcomes in lung cancer patients with or without COPD: a systematic review and meta-analysis

Objectives: This meta-analysis aimed to demonstrate the impact of preoperative exercise therapy on surgical outcomes in patients with lung cancer and COPD. Pulmonary function and muscle capacity were investigated to explore their potential links with outcome improvements after exercise. Methods: Articles were searched from PubMed, Embase, and the Cochrane Library with criteria of lung cancer patients with or without COPD, undergoing resection, and receiving preoperative exercise training. Key outcomes were analyzed using meta-analysis. Results: Seven studies containing 404 participants were included. Patients receiving preoperative exercise training had a lower incidence of postoperative pulmonary complications (PPCs; OR 0.44, 95% CI 0.27-0.71) and shorter length of hospital stay (standardized mean difference -4.23 days, 95% CI -6.14 to -2.32 days). Exceptionally, pneumonia incidence remained unchanged. Patients with COPD could not obviously benefit from exercise training to reduce PPCs (OR 0.44, 95% CI 0.18-1.08), but still might achieve faster recovery. No significant difference in pulmonary function was observed between the two groups. However, 6MWD and VO2 peak were significantly improved after exercise training. Conclusion: Preoperative exercise training may reduce PPCs for lung cancer patients. However, for patients with COPD undergoing lung cancer resection, the role of exercise is uncertain, due to limited data, which calls for more prospective trials on this topic. Rehabilitation exercise strengthens muscle capacity, but does not improve impaired pulmonary function, which emphasizes the possible mechanism of the protocol design.