Background Prophylactic para-aortic nodal dissection （PAND） has no proven benefits for potentially curable advanced gastric cancer.However,the value of therapeutic PAND for involved para-aortic nodes （PANs） in patients with locally advanced gastric cancers has not been determined yet.Methods Between 1998 and 2010,157 gastric cancer patients with 1-3 involved PANs underwent extended D2 （D2＋） lymphadenectomy plus PAND （PAND group,n=69） or extended D2 lymphadenectomy alone （non-PAND group,n=88）.The clinicopathologic features and prognostic data were compared between the two groups.A propensity score-adjusted analysis was used for a balanced comparison.Results The rate of PAN metastasis was 40.6％ （28/69） in the PAND group.The 5-year survival rate was significantly higher in the PAND group than in the non-PAND group （43.7％ vs.31.8％,P=-0.044）.Compared to the non-PAND group,the death hazard ratios in the PAND group were 0.45 （95％ CI 0.274-0.739; P=0.002） and 0.536 （95％ CI 0.328-0.861; P=-0.0097） by multivariate analysis without and with propensity score adjustment respectively.Recurrence rate at 5 years was 39.1％ in the PAND group and 43.2％ in the non-PAND group （P=0.628）.Conclusion Extended D2 lymphadenectomy plus PAND is associated with superior outcomes for advanced gastric cancer patients with 1-3 involved PANs.
