Clinical Impact of Conversion Surgery After Induction Therapy for Esophageal Cancer with Synchronous Distant Metastasis: A Multi-institutional Retrospective Study

BackgroundThe standard treatment for advanced esophageal cancer with synchronous distant metastasis is systemic chemotherapy or immunotherapy. Conversion surgery is not established for esophageal cancer with synchronous distant metastasis. This study aimed to investigate the clinical impact of conversion surgery for esophageal cancer with synchronous distant metastasis after induction therapy.MethodsThis multi-institutional retrospective study enrolled 66 patients with advanced esophageal cancer, including synchronous distant metastasis, who underwent induction chemotherapy or chemoradiotherapy followed by conversion surgery between 2005 and 2021. Short- and long-term outcomes were investigated.ResultsDistant lymph node (LN) metastasis occurred in 51 patients (77%). Distant organ metastasis occurred in 15 (23%) patients. There were 41 patients with metastatic para-aortic LNs, and 10 patients with other metastatic LNs. Organs with distant metastasis included the lung in seven patients, liver in seven patients, and liver and lung in one patient. For 61 patients (92%), R0 resection was achieved. The postoperative complication rate was 47%. The in-hospital mortality rate was 1%, and the 3- and 5-year overall survival (OS) rates for all the patients were 32.4% and 24.4%, respectively. The OS rates were similar between the patients with distant LN metastasis and the patients with distant organ metastasis (3-year OS: 34.9% vs. 26.7%; P = 0.435). Multivariate analysis showed that pathologic nodal status is independently associated with a poor prognosis (hazard ratio, 2.43; P = 0.005).ConclusionsConversion surgery after chemotherapy or chemoradiotherapy for esophageal cancer with synchronous distant metastasis is feasible and promising. It might be effective for improving the long-term prognosis for patients with controlled nodal status.