Background: Multivariate analyses has shown that the status of lymph node metastasis and the depth of tumor penetration through the gastric wall are the most important prognostic factors in patients with advanced gastric carcinoma after curative operation. A clinicopathological study was carried out to clarify a simple and optimal prognostic indicator for early gastric cancer.
Methods: Retrospective analyses of 982 patients with early gastric cancer (562 with mucosal [M] and 420 with submucosal [SM] tumor) treated by gastrectomy with D2 lymph node dissection were performed.
Results: The incidence of lymph node metastasis from M and SM tumors was 2.5% (14/562) and 20.2% (85/420), respectively. There were no apparent prognostic indicators in patients with M tumors. In patients with SM tumors, the cancer-specific 5-year survival of those with lymph node metastasis was significantly lower than that of those without such metastasis (77.6% vs 98.2%; P < 0.001). An sharp decrease in survival was seen between patients with two positive nodes and those with three positive nodes, and the cancer-specific 5-year survival rate of patients with three or more metastatic lymph nodes was significantly lower than that of those with one or two nodes (P < 0.001; univariate analysis). Multivariate analysis revealed that the involvement of three or more lymph nodes was the sole independent prognostic determinant (P = 0.016); the level of nodal metastasis was not an independent prognostic factor (P = 0.384). All patients with N2 lymph node echelons (according to the Japanese Research Society for Gastric Cancer classification of the draining lymph nodes of the stomach) in the group with one or two positive nodes survived for more than 5 years.
Conclusion: The sole independent prognostic factor in SM gastric cancer is the involvement of three or more metastatic lymph nodes. We suggest that this simple prognostic indicator for the follow-up of early gastric cancer, and this could lead to potentially effective adjuvant chemotherapy.