Prognosis Impact And The Pattern Of Solitary Lymph Node Metastasis In Gastric Cancer

Objective To explore the prognosis impact and the pattern of solitary lymph node (LN) metastasis in gastric cancer.Methods clinical data of 280 patients with gastric cancer who underwent D2 radical resection from January 1995 to December 2003 were analyzed retrospectively. Among them, solitary LN metastasis was proven pathologically in 83 cases (solitary LN metastasis group), while node-negative metastasis was proven pathologically in 197 cases (node-negative group). The precise stations of the metastasis LN and their correlation with the location of primary tumor were studied. The 5-year survival rates were compared between two groups and between patients with and without skipping LN metastasis. The prognostic factors were evaluated by univariate and multivariate analyses.Results Among the 83 patients proven solitary LN metastasis, 64 cases (77.1%) presented with the perigastric nodes metastasis (N1 area), For tumors in the upper and middle third stomach, the No.3 station was the most common first metastasized LN station (40.0% and 41.7%, respectively). While for tumors in the lower third stomach, the No.6 station was the mostly affected LN (32.6%). There were 19 cases (22.9%) in N2 area without N1 involvement (skipping LN metastasis), and the NO.7 station was the most common metastasized LN station (42.1%). The 5-year survival rates in the solitary LN metastasis group and the node-negative group were 62.3% and 83.5% respectively with significantly difference (P<0.05). The solitary LN metastasis was one of the independent prognostic factors. Logistic regression revealed that the depth of invasion was independent covariate for solitary LN metastasis. The 5-year survival rates of the patients with and without skipping LN metastasis were 50.0% and 66.1% respectively, there was no significant difference(P>0.05).Conclusions Perigastric nodes are the most common first sites of tumor metastasis, making them the main targets of the operative sentinel lymphatic mapping procedures. The prognosis of patients with solitary LN metastasis is significantly poorer than those without lymph node metastasis. The skipping LN metastasis is common along the left gastric artery and may be correlated with the depth of invasion. Due to the high incidence of skip LN metastasis in gastric cancer, D2 radical resection should be performed to ensure oncological clearance.