Outcome and prognostic analysis of salvage esophagectomy for clinical T4b esophageal squamous cell carcinoma after definite chemoradiotherapy

Background: Definite chemoradiotherapy (dCRT) followed by surgery is a treatment option for clinical T4b esophageal squamous cell carcinoma (ESCC). However, the feasibility and safety of salvage esophagectomy for clinical T4b patients after dCRT remains unclear. This study aimed to analyze the outcomes and prognostic factors of salvage esophagectomy for cT4b ESCC after dCRT. Materials and Methods: From 2008 to 2017, a total of 21 patients who underwent salvage esophagectomy after dCRT for initially unresectable disease at the author\u0027s institution were assessed. The study retrospectively reviewed the baseline characteristics of these cases and evaluated the prognostic factors and surgical outcomes. Results: Among the study group, R0 resection was achieved in 9 patients (43%). The rate of major complications classified as Clavien-Dindo classification (CDc) Grade IIIb or higher was 24.0%. The overall survival (OS) and disease-free survival (DFS) rates were 46% and 25% at 3 years, respectively. Univariate analysis showed that the patients who had R0 resection had a significantly better OS (P = 0.012, 78% vs. 25%) and DFS (P = 0.025, 39% vs. 18%) compared to those with R1/2 resection. The patients with minor complications (CDc ≤ IIIa) had a better OS (P = 0.002, 61% vs. 0%) compared to the group with major complications (CDc ≥ IIIb). The pathological results with earlier T (ypT0-2) were better than with advanced T (ypT3-4) for 3-year OS (P = 0.042, 83% vs. 30%) and 3-year DFS (P = 0.018, 53% vs. 13%). In multivariate analysis, R0 resection (P = 0.042, 95% confidence interval [CI] 1.051–15.617) and CDc ≤ IIIa (P = 0.019, 95% CI 1.286–16.023) were associated with a significantly better prognosis with regards to 3-year OS, and R0 resection was associated with a significantly better prognosis with regards to 3-year DFS (P = 0.0339, 95% CI 1.108–13.136). Conclusion: The results showed that in salvage esophagectomy for T4b ESCC patients after dCRT, R0 resection and CDc ≤ IIIa were favorable prognostic factors. The surgical complications were still high, but this was acceptable in view of the potential long-term survival after salvage esophagectomy. Carefully selecting candidates remains an important issue before surgery.