Based on Siewert classification, adenocarcinomas of the esophagogastric junction （AEGs） have different behaviors of perigastric-mediastinal nodal metastasis. Siewert type I AEGs have higher incidence of mediastinal nodal metastasis than those of type H or III, especially at middle-upper mediastinum. With regard to the necessity of mediastinal lymphadenectomy, theoretically, transthoracic esophagogastrectomy with complete mediastinal lymphadenectomy is suggested for Siewert type I AEGs, while transhiatal total gastrectomy with lower mediastinal and D2 perigastric lymphadenectomy is a standard surgery for type II-III AEGs. Nevertheless, the mediastinal nodal metastasis is an independent factor of poor prognosis for any type of AEG.
Objective： To compare the survival outcomes of transabdominal （TA） and transthoracic （TT） surgical approaches in patients with Siewert-II/III esophagogastric junction adenocarcinoma. Methods： This retrospective study was conducted in patients with Siewert-II/III esophagogastric junction adenocarcinoma who underwent either TT or TA operations in the West China Hospital between January 2006 and December 2009. Results： A total of 308 patients （109 in the TT and 199 in the TA groups） were included in this study with a follow-up rate of 87.3%. The median （P25, P75） number of harvested perigastric lymph nodes was 8 （5, 10） in the TT group and 23 （16, 34） in the TA group （P〈0.001）, and the number of positive perigastric lymph nodes was 2 （0, 5） in the TT group and 3 （1, 8） in the TA group （P〈0.004）. The 5-year overall survival （OS） rate was 36% in the TT group and 51% in the TA group （P=0.005）. Subgroup analysis by Siewert classification showed that 5-year OS rates for patients with Siewert II tumors were 38% and 48% in TT and TA groups, respectively （P=0.134）, whereas the 5-year OS rate for patients with Siewert III tumors was significantly lower in the TT group than that in the TA group （33% vs. 53%; P=0.010）. Multivariate analysis indicated that N2 and N3 stages, RI/R2 resection and a TT surgical approach were prognostic factors for poor OS. Conclusions： Improved perigastric lymph node dissection may be the main reason for better survival outcomes observed with a TA gastrectomy approach than with TT gastrectomy for Siewert III tumor patients.
