The Assessment of the Oncological Safety Margin of Insufficient Lymph Node Dissection in pT2 (pm) Gastric Cancer

Purpose: To identify the effect of insufficient lymph node dissection (LND) on the survival of patients with pT2 gastric cancer. Materials and Methods: A total of 340 patients (120 patients with insufficient LND and others with D2 LND) who underwent gastrectomy for pT2 gastric cancer between January 2008 and December 2010 were included. Results: The incidence of preoperatively diagnosed early gastric cancer was higher and there were fewer metastatic lymph nodes (LNs) in the insufficient LND group than the D2 group, but there was no survival difference between two groups (p=0.365). Among the 89 patients with metastatic LNs after D2 LND, 13 patients (14.6%) had metastatic LNs at selected N2 stations (#10, 11, or 12a), but none of these patients were in the pN1 category. One patient had five metastatic LNs at station #11p with no metastatic LNs at any other stations. The number of metastatic LNs was identified as the only risk factor for LN metastasis at selected N2 stations by logistic regression. Conclusion: If a patient has pN0 or pN1 category after insufficient LND for pT2 gastric cancer, the surgery can be regarded as secure. However, for patients with pN2 or pN3 category, more careful examination is required.