The Prognostic Impact of Minimally Invasive Esophagectomy on Survival after Esophagectomy following a Delayed Interval after Chemoradiotherapy; A Secondary Analysis of the DICE Study

Objective: To evaluate prognostic differences between minimally invasive esophagectomy (MIE) and open esophagectomy (OE) in patients with surgery after a prolonged interval (>12 wk) following chemoradiotherapy (CRT). Background: Previously, we established that a prolonged interval after CRT before esophagectomy was associated with poorer long-term survival. Methods: This was an international multicenter cohort study involving 17 tertiary centers, including patients who received CRT followed by surgery between 2010 and 2020. Patients undergoing MIE were defined as thoracoscopic and laparoscopic approaches. Results: A total of 428 patients (145 MIE and 283 OE) had surgery between 12 weeks and 2 years after CRT. Significant differences were observed in American Society of Anesthesiologists grade, radiation dose, clinical T stage, and histologic subtype. There were no significant differences between the groups in age, sex, body mass index, pathologic T or N stage, resection margin status, tumor location, surgical technique, or 90-day mortality. Survival analysis showed MIE was associated with improved survival in univariate (P=0.014), multivariate analysis after adjustment for smoking, T and N stage, and histology (HR=1.69; 95% CI: 1.14-2.5) and propensity-matched analysis (P=0.02). Further subgroup analyses by radiation dose and interval after CRT showed survival advantage for MIE in 40 to 50 Gy dose groups (HR=1.9; 95% CI: 1.2-3.0) and in patients having surgery within 6 months of CRT (HR=1.6; 95% CI: 1.1-2.2). Conclusions: MIE was associated with improved overall survival compared with OE in patients with a prolonged interval from CRT to surgery. The mechanism for this observed improvement in survival remains unknown, with potential hypotheses including a reduction in complications and improved functional recovery after MIE.