15. EFFECT OF ARTIFICIAL CAPNOTHORAX VS NON-CAPNOTHORAX DURING THORACOSCOPIC ESOPHAGECTOMY ON CIRCULATING TUMOR CELLS AND SURVIVAL IN ESOPHAGEAL CANCER

To investigate the effect of artificial capnothorax on circulating tumor cells and survival after minimally invasive esophagectomy for esophageal cancer. This prospective, multicenter, randomized controlled trial was conducted in a tertiary hospital in China. Between August 2019 and January 2020, 110 patients with resectable esophageal cancer were randomized to undergo non-capnothorax esophagectomy (n = 55) or capnothorax procedures. The analysis was based on the intention-to-treat principle. The final follow-up occurred in November 2022. The main outcomes were changes in folate receptor-positive circulating tumor cells, 3-year overall survival, and disease-free survival rates. A total of 110 patients were included in the intention-to-treat analysis. After surgery, the incidence of patients with incremental changes in FR + CTC levels was 18.6% (8/43) in the capnothorax group and 2.7% (1/37) in the non-capnothorax group (P = 0.033) (mean changes, −3.9 ± 3.4 [FU/3 mL] vs −2.4 ± 2.9 [FU/3 mL], respectively; P = 0.039). There were significant differences in the 3-year overall survival rate (81.6% [95%, 72.4–92.0] vs 65.2% [95%, 59.3–78.8]; P = 0.002) and disease-free survival rate (81.6% [95%, 72.4–93.0] vs 61.6% [95%, 50.1–75.7]; P = 0.015) between the two groups. Multivariate analysis indicated that the artificial pneumothorax approach was a prognostic factor for overall survival (HR: 2.347, 95% CI: 1.053–5.235; P = 0.037) and disease-free survival (HR: 1.325, 95% CI: 1.210–1.451; P < 0.001). Artificial capnothorax during surgery resulted in increased dissemination of circulating tumor cells and worse survival outcomes in patients with esophageal cancer. Esophagectomy under non-capnothorax should be a recommended procedure.