Suprapancreatic nodal dissection should not be uniformly selected in additional gastrectomy for the patients who diagnosed as pT1b gastric cancer by endoscopic resection.

BACKGROUND: Surgery for T1b gastric cancer requires suprapancreatic nodes (SPA nodes) and perigastric nodes (PG nodes), however, SPA nodal dissection can cause pancreatic complications. If endoscopic treatment followed by additional surgery is planned, it may be possible to predict SPA nodal metastasis by analyzing the pathological information of the primary tumor in addition to the clinical findings.

METHODS: Patients who underwent D1+ or D2 and who were pathologically diagnosed with pT1b were retrospectively analyzed. The stations were divided into the nodes located at the perigastric area (PG nodes; #1-7) and the nodes located at the suprapancreatic area (SPA nodes; #8a-12a). The patients were classified into those with and without metastasis to the SPA nodes. Clinicopathological factors were investigated for their possible association with metastasis to the SPA nodes.

RESULTS: A total of 2017 patients were examined in this study. Metastasis to the SPA nodes was observed in 80 patients (4%). In a multivariate analysis, undifferentiated histology, lower third, and lymphovascular invasion were independent risk factors for metastasis to the SPA nodes. The risk of metastasis to the SPA nodes was <2% in upper/middle tumors of differentiated type with no lymphovascular invasion and in lower tumors of undifferentiated type with no lymphovascular invasion. On the other hand, the risk of metastasis to the SPA nodes was >10% in lower tumors of undifferentiated type with lymphovascular invasion.

CONCLUSION: SPA nodal metastasis can be predicted when endoscopic treatment is initially planned. SPA nodal dissection should not be uniformly selected for T1b gastric cancer.