F-103
PRIORITY OF LYMPH NODE DISSECTION AND SURGICAL APPROACH FOR SIEWERT TYPE II ADENOCARCINOMA OF THE OESOPHAGOGASTRIC JUNCTION: A SINGLE-CENTRE RETROSPECTIVE COHORT STUDY

Objectives: The aim of this study was to compare the clinicopathological characteristics of patients with Siewert type II adenocarcinoma of the oesophagogastric (AOG) who underwent surgery in three different approaches, to identify the optimal extent of thoracic and abdominal lymph node dissection and its surgical approach.

Methods: The clinicopathological data of 192 patients with Siewert II AOG who were admitted to our centre during January 2007 through October 2011 and underwent different surgical procedures were retrospectively analysed. The extent of dissection and metastatic frequency of each lymph node station were reviewed. We used the index of estimated benefit from lymph node dissection to assess the therapeutic value of lymph node dissection of each station.

Results: Overall, for the thoracic lymph node dissection, the left thoracic route and Ivor-Lewis procedure are better choices than the abdomino-transhiatal route (AT). While for the abdominal lymph node dissection, the AT achieved a better dissection extent. No significant difference was found in metastatic frequency for each station except the 16^th station. The 5-year overall survival rate was 46%. The multivariate analysis found only N stage (P = 0.000, HR = 1.67, 95% CI: 1.31-2.14) and the number of resected lymph nodes ≥12 (P = 0.035, HR = 0.58, 95% CI: 0.34-0.96) were prognostic factors for Siewert type II AOG. Furthermore, we identified 2 thoracic lymph node stations (8M and 8L) and 6 abdominal lymph node stations (16, 17, 19, 20, G3, G4) that have a high therapeutic value for the patients.

Conclusions: We recommend that the 8M, 8L, 16, 17, and G3 should be excised for Siewert type II AOG. Although we did not find any survival difference among the three surgical approaches, considering the lymphadenectomy, we may recommend the Ivor-Lewis procedure as the optimal choice for patients with Siewert type II AOG. However, it should be conducted by a thoracic surgeon who is familiar with abdominal lymph node anatomy.

Disclosure: No significant relationships.