Clinical Significance of Metastasis or Micrometastasis to the Lymph Node Along Superior Mesenteric Vein in Gastric Carcinoma: a Retrospective Analysis

Background: The validity of lymphadenectomy of the lymph node along the superior mesenteric vein (LN14v) in gastric cancer remains controversial. The study investigated the characteristics and prognosis of gastric cancer with metastasis or micrometastasis to LN14v. Methods: : A retrospective study of 626 patients receiving radical gastrectomy in our center from January 2003 to December 2015 was analyzed. Totally, 303 patients receiving lymphadenectomy of 14v and lymph node micrometastasis was evaluated by immunohistochemical staining for cytokeratinnodes CK8/18. Logistic regression model was applied to confirm the predictive factors of micrometastasis. Survival analysis was performed to evaluate the effect of micrometastasis or metastasis on prognosis. Results: : The metastastic rate of No.14v lymph node was 15.8% and the micrometastatic rate was 3.9%. Multivariate analysis showed site, Borrmann classification, postoperative lymph node metastasis (pN), the metastasis of LN6 and LN9 were predictive factors of LN14v micrometastasis or metastaticsis ( P <0.05). The 5-year survival rate of positive group (14v micrometastasis or metastasis) was 12.4%. The prognosis of patients without micrometastatic 14v lymph node was better than positive group. While the difference between group of LN14v micrometastasis and LN14v metastasis was not obvious. In matched analysis, patients with gastric cancer of stage Ⅲ, U/M area, pN2-3 and LN 6(+) underwent lymphadenectomy of 14v suffered better survival than those without lymphadenectomy of 14v. Conclusion: Lymph node micrometastasis could provide accurate prognostic information for patients with GC. Thus, lymphadenectomy of LN14v should be recommended for patients with gastric cancer of stage Ⅲ, U/M area, pN2-3 and LN 6(+).