Prognostic Significance of the Number of Negative Lymph Nodes in Postoperative Locally Advanced Gastric Cancer Patients

摘要

OBJECTIVE To evaluate the impact of the number of negativelymph nodes on disease free survival (DFS) in patients with locallyadvanced gastric cancer.METHODS A total of 485 patients who underwent surgeryfor locally advanced gastric cancer (pT3N0-2M0) and had a DFSat least 6 months were enrolled in this retrospective study. Themedical records of the patients were reviewed in detail, andthe characteristics of the patients and the findings of pathologicexamination were analyzed in order to find the potentialassociation with DFS. Subgroup analysis according to pathologicstage was performed. Multivariate analysis using the COXregression method was also conducted in order to identify theindependent prognostic factors. The Kaplan-Meier method wasused to plot DFS curves. The DFS rate was compared in eachsubgroup.RESULTS COX regression analysis showed that the DFS rateof gastric cancer patients with pathologic stage T3N0-2M0 wassignificantly associated with age, degree of tumor differentiation,tumor location as well as the number of negative lymph nodes.Among patients with stage T3N0M0 disease, who had 1-4 and 5or more negative lymph nodes, the 2-year DFS rate was 8.3% and55.6%, respectively. Meanwhile, the 3-year DFS rates of the samegroup of patients was 0% and 24.9%, respectively (P = 0.025). Inthe T3N1M0 subgroup, the 2-year DFS rate of patients with 3or fewer, 4-9, and 10 or more negative lymph nodes was 17.3%,39.1%, 52.6%, respectively. The 3-year DFS rate in this groupwas 4.2%, 6.0%, 17.1%, respectively (P < 0.001). In the T3N2M0subgroup, the 2-year DFS rate of patients with 7 or fewer and 8or more negative lymph nodes was 11.5% and 35%, respectively.The 3-year DFS rate of the same group of patients with 8 or morenegative lymph nodes was also significantly improved (0.8% vs.5%, respectively; P = 0.015).CONCLUSION For gastric cancer patients with pathologicstage T3N0-2M0, the number of negative lymph nodes is anindependent prognostic factor for DFS. The number of negativelymph nodes may reflect the level of regional lymph nodedissection or the accuracy of the pathologic staging.