Clinical impact of postoperative changes in body composition on long-term outcomes in patients with esophageal cancer.

ABSTRACT

BACKGROUND & AIMS: This study aimed to investigate the temporal changes in body composition following esophagectomy in patients with esophageal cancer using bioelectrical impedance analysis and to assess the prognostic implications of these changes. METHODS: Our study included 528 patients who underwent esophagectomy and preoperative body composition measurements between January 2013 and June 2020. Postoperative body composition was measured in 493 patients at discharge as follows 184 at 1 month, 144 at 2 months, 143 at 3 months, 103 at 6 months, 58 at 9 months, and 78 at 12 months. RESULTS: Body weight (BW) continuously decreased until the 6 postoperative months (POMs), reaching -11.5% compared with preoperative levels. Subsequently, almost no change was observed at 12 POMs. Skeletal muscle mass (SMM) decreased until 3 POMs but gradually recovered after 3 POMs. Conversely, body fat mass (BFM) consistently decreased over time post-esophagectomy. The patients were categorized into moderate (>-10%) and severe (≤-10%) groups based on % BW, % SMM, and % BFM losses at 3 POMs. Severe SMM loss at 3 POMs correlated with reduced overall survival (OS) (3-year OS 85.9% in moderate vs. 75.1% in severe, p = 0.035). BFM loss was associated with reduced recurrence-free survival (3-year RFS 83.3% in moderate vs. 62.0% in severe, p = 0.011). Multivariate analysis identified pStages Ⅲ and Ⅳ, % SMM loss ≤ -10%, and % BFM loss ≤ -10% as independent factors for worse OS. CONCLUSION: Post-esophagectomy, distinct temporal changes in BW, SMM, and BFM are observed. Significant reductions in SMM and BFM 3 POMs indicate a poor long-term prognosis.