RESUMO
Objective: To analyze the association of No.11p posterior lymph node metastasis with clinicopathological features and its prognostic significance in gastric cancer. Methods: A single-center retrospective cohort study was conducted. Clinicopathological data of patients with primary gastric cancers undergoing No.11p posterior lymph node dissection from January 2016 to December 2020 were retrieved from the Database of Gastric Cancer, West China Hospital, Sichuan University. Case inclusion criteria: (1) gastric cancer proved by pathology; (2) radical resection with intraoperative No.11p posterior lymph node dissection; (3) operations performed by the same surgical team; (4) no previous history of other malignant tumors and no concurrent malignant tumors. Those with stump gastric cancer, history of gastrectomy, neoadjuvant chemotherapy, incomplete clinicopathological data and lost to follow-up were excluded. During the operation, the upper edge of the pancreas was retracted forward to expose the area between the upper edge of the pancreas and the splenic vessels. The proximal segment of the splenic artery was skeletonized to remove lymphatic tissue anterior and superior to the splenic artery for No.11p lymph node dissection. For patients with lymphadenopathy in the area between the splenic artery and the splenic vein, dissection was performed. The enlarged lymph nodes were labeled with titanium clips and named as No.11p posterior lymph node. Pathological examination was performed separately after the specimen was isolated. Statistical analysis was performed using R software. Results: A total of 127 gastric cancer patients, who underwent No.11p posterior lymph nodes dissection were included in this study, of which 120 patients without No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes negative) and 7 patients with No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes positive). A total of 8 metastatic No.11p posterior lymph nodes were detected in 7 patients, metastasis rate and with a ratio of 5.5% (7/127) and 6.8% (8/127), respectively. In the subgroup analysis of T3-4 stage patients, the metastasis rate and ratio of No.11p posterior lymph nodes were 9.0% (7/78) and 10.7% (8/75), respectively. Compared to negative cases, patients with No.11p posterior lymph nodes metastasis had larger tumor (P=0.002), higher proportion of Borrmann type Ⅲ and Ⅳ tumors (P=0.005), more metastatic lymph nodes (P<0.001), more advanced T stage (P=0.043), N stage (P=0.004) and TNM stage (P=0.015). In survival analysis, patients with No.11p posterior lymph node metastasis had a significantly worse prognosis than those without metastasis after adjusting for TNM stage (hazard ratio=3.009, 95% confidence interval: 1.824-4.964, P<0.001). Conclusions: The No.11p posterior lymph node metastasis in gastric cancer is associated with worse prognosis. For patients of T3-4 stage gastric cancer, No.11p posterior lymph node dissection should be emphasized during radical operation.