Reducing Thoracic Operative Time to Mitigate Post-Esophagectomy Pneumonia: A Retrospective Cohort Study of an Institutional Transition from RAMIE to C-MIE/VATS

Background: Postoperative pneumonia after esophagectomy is associated with worse postoperative recovery and long-term survival. At our institution, robot-assisted minimally invasive esophagectomy (RAMIE) was introduced in 2018 but was associated with prolonged thoracic operative time and frequent pneumonia; therefore, we adopted a conventional minimally invasive thoracic approach using video-assisted thoracoscopic esophagectomy (C-MIE/VATS) from 2024. Methods: We retrospectively analyzed 145 consecutive patients who underwent esophagectomy between January 2014 and November 2025. Thoracoscopic cases were stratified by era as pre-2024 (V-1) and from 2024 onward (V-2) and compared with the RAMIE group (R). The primary endpoint was postoperative pneumonia within 30 days after surgery, diagnosed using clinical and radiologic criteria (fever and inflammatory response with new pulmonary infiltrates on chest radiography or computed tomography) and graded using the Clavien–Dindo classification; events of CD grade ≥ II were counted for the primary analysis. Secondary endpoints included operative variables, postoperative complications, sputum culture findings, and overall survival (OS). Factors associated with pneumonia were evaluated using uni- and multivariable analyses, and OS was assessed using the Kaplan–Meier method. Results: Among 145 patients (V-1, n = 62; R, n = 54; V-2, n = 29), thoracic operative time was shorter in V-2 than in R (median 194 vs 322 min; p < 0.001). Postoperative pneumonia within 30 days occurred in 20.7% (6/29) of V-2 and 40.7% (22/54) of R (p = 0.089); pneumonia rates differed across the three groups (V-1 17.7%, R 40.7%, V-2 20.7%; p = 0.014). Patients who developed pneumonia had worse overall survival than those without pneumonia (5-year OS 22.8% vs 54.4%; log-rank p = 0.038), and pneumonia was associated with increased mortality in a Cox model (HR 1.81, 95% CI 1.02–3.20). Conclusions: Transition to C-MIE/VATS was associated with substantially shorter thoracic operative time and a numerically lower incidence of postoperative pneumonia. Given the observed association between postoperative pneumonia and worse overall survival, efforts to optimize operative efficiency and strengthen pneumonia-prevention strategies warrant further evaluation.