Prognostic impact of para-aortic lymph node involvement in solid pancreatic ductal adenocarcinoma and malignant intraductal papillary mucinous neoplasm

Abstract

Purpose: Para-aortic lymph nodes (PALN) metastases in solid pancreatic ductal adenocarcinoma (sPDAC) indicates short survival. In malignant intraductal papillary mucinous neoplasms (mIPMN) the role of PALN has not been well explored. The present study investigated the rate of metastatic PALN, N status, and lymph node (LN) ratio as prognostic factors in sPDAC and mIPMN. Method: This consecutive single-center series included patients with sPDAC and mIPMN in the pancreatic head who underwent pancreatoduodenectomy or total pancreatectomy including PALN resection during a ten-year period, 2009-2018. Median overall survival (mOS) and impact of clinicopathological factors including PALN status on survival were evaluated. Results: There were 403 patients, of which 89 had mIPMN and 314 sPDAC. PALN were metastatic in 16% of sPDAC and 17% of mIPMN (p=0.962). N0 status was present in 6% and 16%, respectively (p=0.007). A LN ratio>15% was more common in sPDAC (52%) than in mIPMN (34%) (p=0.004). The mOS was 12.7 months in the presence of PALN metastases and 22.7 months without (p<0.0001)(Figure). Age>70 years, CA19-9>200, sPDAC and N2 status were significant in multivariable analysis but PALN status and LN ratio were not independent prognostic factors. There was no difference in mOS in N2 status regardless the presence of PALN metastases. Conclusion: The frequency of PALN metastases was similar in sPDAC and mIPMN. Although mOS was shorter in PALN positive status it was not an independent risk factor and in N2 disease PALN metastases did not influence survival.