Patient selection for salvage surgery after definitive chemoradiotherapy in esophageal squamous cell carcinoma.

Purpose: With the widespread use of definitive chemoradiotherapy (dCRT) for esophageal squamous cell carcinoma (ESCC), salvage surgery for recurrence/residual patients became prevalent. However, survival impact of salvage surgery remains obscure at present.
Methods: The updated clinical outcomes of salvage surgery were investigated to know its survival impact. Of the 155 ESCC patients who underwent dCRT between 2009 and 2016, we included 85 patients with recurrence or residual disease. The median follow-up was 65 months.
Results: Of the 85 patients with progression disease, there were 42 and 43 patients of recurrence and residual disease, respectively. Salvage surgery was performed in 27 patients after dCRT, including 15 patients who underwent salvage esophagectomy. The 5-year overall survival (OS) of salvage surgery and otherwise patients was 66.1% and 14.5%, and the patients with salvage surgery had a significantly better prognosis (p < 0.0001). In the 15 patients who underwent salvage esophagectomy, residual disease, lymph node metastasis-positive (ycN+) after dCRT, and pathological lymph node metastasis-positive (ypN+) were significantly associated with poor prognosis (p = 0.0492, p = 0.0006, p = 0.0276), and the 5-year OS rates for the ycN/ypN combinations were 90%, 33.3%, and 0% in ycN-/ypN-, ycN+/ypN-, and ycN+/ypN+ patients, respectively (p = 0.0026). In a multivariate analysis, ycN+ was an independent poor prognostic factor (HR 13.6, 95% CI 1.65-286.8, p = 0.0154).
Conclusions: Survival impact of salvage surgery after dCRT is robust, and lymph node metastasis after dCRT may help determine the indication for salvage esophagectomy.