OBJECTIVETo study the correlation between characteristics of lymph node metastases and prognosis in pancreatic cancer treated with pancreaticoduodenectomy.

METHODSThe clinicopathological data of consecutive series of 122 patients who underwent resection for adenocarcinoma of the pancreas with lymphadenectomy in our hospital were reviewed in this study. The number of metastatic lymph nodes, lymph node metastasis ratio, lymph node levels, and other clinocopathological factors were analyzed by Kaplan-Meier method and Cox proportional hazard model, and their correlation with prognosis was also analyzed.

RESULTS122 patients met the inclusion criteria and entered the study. There were 90 patients (73.8%) with lymph node metastases. Median (range) metastatic lymph node number was 7 (1-28) for the entire cohort, and median (range) metastatic lymph node ratio was 21.1% (3.6%-62.2%). The numbers of patients with lymph nodes metastases to levels 1, 2, 3 were 39 (43.3%), 40 (44.4%), and 11 (12.2%), respectively. Univariate analysis suggested that the maximum diameter of tumor, lymph node metastases, number, ratio, level, distant metastases and adjuvant chemotherapy were significantly related to survival in the entire cohort (P < 0.05). The maximum diameter of tumor, lymph node metastasis number, ratio, level, and adjuvant chemotherapy were significantly related to the survival in node-positive patients (P < 0.05). Multivariate analysis suggested that the diameter of tumor >2 cm, lymph node metastases, metastatic lymph node number >2, ratio >20%, level >1, and without adjuvant chemotherapy were independent risk factors of survival in the entire cohort (P < 0.05). The maximum diameter of tumor >2 cm, metastatic lymph node number >2, ratio >20%, level >1 and without adjuvant chemotherapy were independent risk factors of survival in node-positive patients (P < 0.05 for all).

CONCLUSIONSThe three indexes, metastatic number, ratio and extent of lymph nodal involvement are statistically significant prognostic factors in pancreatic cancer, which can complement the existing lymph node metastasis staging. The standardized pancreaticoduodenectomy combined with proper lymphodenectomy provides an important basis for a correct prognostic evaluation.