P1.239. Clinical Outcomes of Conversion Surgery for Locally Advanced Esophageal Cancer With Mediastinal M1b Lymph Node Metastasis

Topic Esophageal Cancer: Surgical Treatment of Esophageal Cancer – long term outcomes Background The role of conversion surgery (CS) for locally advanced esophageal cancer with mediastinal M1b lymph node metastasis has not yet been clearly defined. Methods We evaluated the therapeutic outcomes of 27 patients who underwent conversion surgery (CS) for locally advanced esophageal cancer with mediastinal M1b lymph node metastasis, among 1,030 patients who underwent thoracic esophagectomy at our institution between January 2011 and November 2023. Results The number of patients with mediastinal M1b lymph node metastases (114/113/106pre/106tbR/112Ao-P) were 12/4/12/12/1/4, respectively (duplicate results). Preoperative therapy (CF/DCF/CRT) was administered to 7/15/4 patients, respectively. The response rate of preoperative treatment was 85%. Postoperative adjuvant chemotherapy (none/Nivo) was given in 0/3 of the patients. Short-term postoperative outcomes were suture failure in 4 patients (15%), pneumonia in 7 patients (27%), recurrent nerve palsy in 4 patients (15%), and no in-hospital death. Postoperative recurrence was observed in 15 patients (56%). The 3-year postoperative recurrence-free survival (PFS) rate was 52%, and the 3-year overall survival (OS) rate was 63%. 3-year PFS by distant lymph node (114 or 113 node/106pre or 106tbR node/112Ao-P node) was 60%/23%/75%, respectively. The 3-year OS was 67%/38%/75%, respectively. The short-term postoperative outcomes were acceptable in all cases, with 113/114 lymph node metastases and 112Ao-P metastases having a relatively better prognosis than 106pre/106tbR metastases. Conclusion CS may have significance in locally advanced esophageal cancer with mediastinal M1b lymph node metastasis as part of multimodality treatment in the case of anterior mediastinal lymph node metastasis and 112Ao-P.