OBJECTIVETo investigative the influencing factors of metastatic lymph node staging (N staging), and the effect of number of lymph node dissection on the prognosis in advanced gastric carcinoma.

METHODSClinicopathological data of 395 advanced gastric cancer patients undergoing radical operation in Harbin Medical University Cancer Hospital in 2011 were retrospectively analyzed. Logistic regression was used to investigate the influencing factors. Cox model was used to evaluate the prognostic factors. Association of survival with the number of lymph node dissection in different N stage was further examined.

RESULTSLymph node metastasis was found in 307 patients(77.7%), including 88 of N0, 86 of N1, 111 of N2 and 110 of N3. Overall 3-year survival rate was 65.3%. Borrmann classification (χ(2)=32.045, P=0.000), histopathological type (χ(2)=5.595, P=0.018), depth of invasion (χ(2)=27.227, P=0.000) and the number of lymph node dissection (χ(2)=12.337, P=0.000) were influencing factors of metastatic lymph node. Tumor location(OR=2.86, 95% CI: 1.80~4.53, P=0.000), depth of invasion (OR=1.44, 95% CI: 1.12~1.85, P=0.004) and the number of metastatic lymph node (OR=1.58, 95% CI: 1.33~1.87, P=0.000) were independent prognostic factors(all P < 0.05), and number of lymph node dissection was not associated with prognosis (P > 0.05). Subgroup analysis revealed overall survival rate of stage N3 patients with ≥ 40 of lymph node dissection was obviously higher as compared to those with < 40, while such difference was not found in N0, N1, N2 groups (all P > 0.05).

CONCLUSIONSLymph node staging of advanced gastric cancer is associated with Borrmann classification, histopathological type, depth of invasion and number of lymph node dissection. Dissection of 20 lymph nodes is suitable for stage N0, N1 and N2, while ≥ 40 lymph nodes should be dissected in stage N3.