Prognostic significance of the number of dissected lymph nodes in Siewert type Ⅱadenocarcinoma of the esophagogastric junction without lymphatic metastasis

Abstract

To investigate the correlation between the number of dissected lymph nodes (LNs) and the prognosis of patients with node-negative Siewert type ⅡAEG. 248 patients with Siewert type Ⅱ AEG treated in our hospital between January 1998 and December 2008 were retrospectively assessed. All cases underwent left transthoracic subtotal esophagogastrectomy with conventional two-field lymphadenectomy, and were histopathologically proved to be without lymph node involvement. The prognostic impact of the number of dissected LNs was analyzed. The overall median survival time and the 1-, 3-, and 5-year overall survival rates were 64 months, 80.4%, 60.8% and 51.0%, respectively. Cox regression showed that the number of dissected LNs and the depth of tumor invasion were independent prognostic factors. Patients with a high number of negative LNs had better overall survival than patients with a low number of negative LNs (P<0.05). The patients had better long-term survival outcomes with more than 10 LN dissected for cases with pT1 tumor (P<0.001), and so did those with more than 15 LN dissected for cases with pT2-3 tumor (P=0.003, 0.018, respectively). The number of negative lymph nodes and the depth of tumor invasion are independent prognostic factors for node-negative Siewert type Ⅱ AEG, and adequate lymph node dissection can improve the long-term survival.