Abstract
BACKGROUND: The optimal lymphadenectomy for gastric cancer (GC) with pyloric invasion is controversial because the pattern of lymph node metastasis is different from that of distal GC. The rate of lymph node metastasis into the posterior area of the pancreatic head and hepatoduodenal ligament is high. This study evaluated the estimated benefit of radical gastrectomy with D2-plus lymphadenectomy in patients with pyloric invasion. METHODS: All patients with GC invading the pylorus who underwent curative surgical resection with D2-plus lymphadenectomy between February 2013 and September 2015 were enrolled in the study. The index of estimated benefit from lymph node dissection (IEBLD) was calculated by multiplying the incidence of metastasis to each lymph node station by the 3-year overall survival (OS) rate of patients with metastasis to that station. RESULTS: In total, 128 patients were eligible. The rate of lymph node metastasis and the 3-year OS rate (and IEBLD) of the patients with metastasis to lymph nodes were 14.3 and 44.4% (5.56) for No. 8p, 10.9 and 35.7% (3.89) for No. 12b, 9.5 and 33.3% (3.13) for No. 12p, 18.8 and 54.2% (10.19) for No. 13, and 21.8 and 53.6% (11.68) for No. 14v, respectively. CONCLUSIONS: In radical gastrectomy for GC with pyloric invasion, some survival benefit was observed with dissection of the No. 13 and No. 14 lymph nodes, but there was no survival benefit with dissection of the No. 8p lymph nodes. The No. 12b and No. 12p lymph nodes may be better to dissect in cT3 GC patients with pyloric invasion. TRIAL REGISTRATION: http://ClinicalTrials.gov Identifier: NCT01836991. Date of registration: April 17, 2013.