Effect of splenic hilar lymphadenectomy on locally advanced Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction with a tumor diameter ≥4 cm: a five-year survival analysis

Abstract

Objective: To examine the long term outcome of splenic hilar lymphadenectomy (SHL) for locally advanced Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG) with a tumor diameter ≥4 cm. Methods: A total of 489 locally advanced Siewert type Ⅱ and Ⅲ AEG patients with a tumor diameter ≥4 cm who underwent radical resection from January 2010 to April 2016 were included. There were 383 males and 106 females. There were 225 patients aged≥65 years and 264 patients aged <65 years. SHL was conducted in 270 patients(SHL group). Wilcoxon rank-sum test or χ2 test were conducted for inter-group comparison. Cox proportional hazard regression was used to analyze the long term outcome of SHL and the prognosis factors of overall survival. Kaplan-Meier curve was drawn finally. The results of survival analysis were verified by Log-rank test. Results: Followed-up to April 2021,the median follow-up time was 78.0 months (range: 74.0 to 85.0 months), the follow-up rate was 95.5%(467/489). The splenic hilar lymphnode metastasis rate of the SHL group was 12.6% (34/270). Younger patients (<65 years old), less complications, higher proportion of patients received adjuvant chemotherapy were demonstrated in the SHL group (χ2: 5.644 to 6.744, all P<0.05). Multivariate analysis showed that SHL was the independent prognosis factor of overall survival for patients with Siewert type Ⅱ and Ⅲ AEG and a tumor diameter≥4 cm (HR=0.68, 95%CI: 0.52 to 0.88, P=0.004) along with preoperative CA19-9, pathological T stage, pathological N stage, adjuvant chemotherapy and postoperative complication. Further subgroup analysis demonstrated that the SHL group had better 5-year overall survival than non-SHL group (62.4% vs. 39.2%, χ2=17.983, P=0.006) in Siewert type Ⅲ AEG rather than in Siewert type Ⅱ AEG(57.3% vs. 53.7%, χ2=3.031, P=0.805). Conclusion: In experienced center, splenic hilar lymphadenectomy can improve the prognosis of Siewert type Ⅲ AEG with a tumor diameter ≥4 cm.