Prognostic Factors and Appropriate Lymph Node Dissection in Salvage Esophagectomy for Locally Advanced T4 Esophageal Cancer.

ABSTRACT

BACKGROUND: A suitable treatment strategy for esophageal cancer after definitive chemoradiotherapy for T4 cases has not been established and remains unclear. This study aimed to clarify the independent prognostic factors, surgical indications, and optimal extent of lymphadenectomy for T4 esophageal cancer. METHODS: Of 803 patients who underwent esophagectomy for esophageal cancer at the authors' institution from 2006 to March 2018, the study included 33 patients who underwent salvage esophagectomy with locally advanced T4 cancer. The study examined the baseline attributes and treatment results of these cases and evaluated the prognostic factors and treatment strategies. RESULTS: The independent favorable prognostic factors in T4 cancer (T4a/T4b = 11/22) included non-T4b status [hazard ratio (HR), 15.311; 95% confidence-interval (CI), 1.277-183.5] and R0 resection (HR, 14.706; 95% CI, 1.193-166.67). For the cases in which R0 resection was possible (n = 14), both the 1- and 5-year survival rates were 90.9%, whereas for the cases without R0 dissection (n = 19), the 1- and 5-year survival rates were respectively 44.9% and 0%. In the univariate analysis, the patients who underwent two- or three-field lymph node dissection tended to have a better prognosis (p = 0.062), and those with 60 or more lymph nodes dissected had a significantly better prognosis (p = 0.038). For the patients who underwent salvage esophagectomy with typical lymph node dissection, the rate of complications classified as Clavien-Dindo grade 3 or higher (33.3%) was not increased, indicating that the procedure was relatively safe. CONCLUSIONS: The results showed that in salvage esophagectomy for T4 esophageal cancer, R0 resection led to improved prognosis. Because typical two- or three-field lymph node dissection including prophylactic dissection could be performed safely and led to a better prognosis in salvage esophagectomy, typical esophagectomy including prophylactic lymph node dissection should be performed if possible.