Advantageous factors of R0 curative conversion esophagectomy and the optimal extent of lymphadenectomy after induction therapy for cT4b thoracic esophageal cancer

AIM

This study aimed to clarify the prognostic factors, the advantageous factors of R0 curative resection, and optimal extents of lymph node dissection for conversion esophagectomy after induction therapy.

METHODS

Among 1903 patients with esophageal cancer at Toranomon Hospital between January 2006 to May 2020, 151 patients with locally advanced T4b thoracic esophageal cancer were divided into two groups according to treatment: conversion surgery group (n = 54) and non-surgical treatment group (n = 97) for comparison.

RESULTS

The patients who underwent R0 curative resection showed preferable survival comparable to the survival rate of patients with cCR in the non-surgical treatment group (1-, 3- and 5-year survival: 96.9%, 82.1% and 76.7% vs 94.1%, 86.3%, and 86.3%; P = 0.770). Multivariate analysis revealed that the T4b tumor invasion by primary site (odds ratio (OR) = 6.100; 95% CI, 1.439-25.865: P = 0.014) and time to conversion surgery from start of induction therapy within four months (OR = 5.229; 95% CI, 1.296-21.102: P = 0.020) were all independent advantageous factors of R0 curative resection. Actuarial 1-, 3- and 5-year survival rates in patients who underwent conversion surgery with D2-3 lymphadenectomy were 90.9%, 48.6%, and 40.8%, respectively.

CONCLUSIONS

R0 resection led to improved prognosis in conversion esophagectomy for cT4b esophageal cancer. The T4b tumor invasion by primary site and time to conversion surgery from start of induction therapy within 4 months were independent advantageous factors of R0 curative resection. In addition, standard radical esophagectomy including prophylactic D2-/3- lymphadenectomy should be performed if it is possible, while taking adequate care regarding the increased risk after induction therapy.

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

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.