Adjuvant chemotherapy in node‐positive patients after esophagectomy for esophageal squamous cell carcinoma

BACKGROUND: The role of adjuvant chemotherapy in esophageal squamous cell carcinoma (ESCC) remains controversial. This study aimed to evaluate the impact of adjuvant chemotherapy on survival in patients with positive nodes after surgery for ESCC. METHODS: We retrospectively reviewed the survival outcomes of node‐positive patients with ESCC who underwent curative resection with or without adjuvant chemotherapy between January 1994 and December 2015. RESULTS: We analyzed 460 patients (333 adjuvant chemotherapy, 127 surgery alone). The surgery‐alone group was older (64 vs. 60 years, p < 0.001) and had more comorbidities (p = 0.004) than the adjuvant chemotherapy group. After propensity score matching, overall survival (OS) and recurrence‐free survival (RFS) of the adjuvant chemotherapy group were better than those of the surgery‐alone group: 5‐year OS rate 62.7% (95% confidence interval [CI] 54.4–72.3%) vs. 46.8% (95% CI 38.5–57%, p = 0.001) and 5‐year RFS rate 53.9% (95% CI 45.4–63.9%) vs. 36.2% (95% CI 28.3–46.3%, p < 0.001). Notably, in patients with pT3–4 stage, the adjuvant chemotherapy group had significantly better 5‐year OS rate (41.3% [95% CI 29.3–58.3%] vs. 18% [95% CI 10–32.5%], p = 0.01) and 5‐year RFS rate (37% [95% CI 25.3–53.9%] vs. 12% [95% CI 5.7–25.4%], p < 0.001) than in the surgery‐alone group. In multivariable analysis, adjuvant chemotherapy had a favorable effect on both OS (hazard ratio [HR] 0.562, 95% CI 0.426–0.741, p < 0.001) and RFS (HR 0.702, 95% CI 0.514–0.959; p = 0.026). CONCLUSION: Adjuvant chemotherapy may improve survival in node‐positive patients with ESCC, especially in those with pT3–4 stage.