title: Prognostic impact of nodal statuses in patients with pancreatic ductal adenocarcinoma.
abstract: BACKGROUND
  The present study aimed to clarify the prognostic impact of nodal statuses in pancreatic ductal adenocarcinoma (PDAC) after potentially curative pancreatectomy.
  
  
  METHODS
  In 110 patients with >10 examined lymph nodes (ELNs), we investigated how nodal statuses were associated with postoperative survival. Nodal statuses included the number of positive LNs (PLNs); the ratio of PLNs to ELNs (lymph node ratio; LNR); and the location of regional LN metastases, classified as group one (peripancreatic area) and group 2 (outside the peripancreatic area). The maximum χ2value, provided by a Cox proportional hazards model, was used to determine the optimal cutoff value for the number of PLNs and the LNR.
  
  
  RESULTS
  The median numbers of ELNs and metastatic LNs were 33 and 2, respectively. Median survival was longer in patients with ≤3 PLNs (37.5 months), LNR <0.11 (36.1 months), and group 1 LN metastases (37.5 months) compared to in patients with ≥4 PLNs (23.7 months), LNR ≥0.11 (23.9 months), and group 2 LN metastases (22.8 months), respectively. Multivariate analyses revealed that all three investigated nodal statuses were independent factors associated with survival: HR of 2.38 and p = 0.0006 for the location of LN metastases, HR of 1.92 and p = 0.0071 for the number of PLNs, and HR of 1.89 and p = 0.010 for the LNR.
  
  
  CONCLUSIONS
  Three nodal statuses-the number of PLNs, the LNR, and the location of LN metastases-could stratify postoperative survival among PDAC patients with an adequate number of examined LNs after pancreatectomy.
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan; Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Yasunari
authors.initials: Y
authors.lastname: Fukuda
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Tadafumi
authors.initials: T
authors.lastname: Asaoka
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan.
authors.forename: Sakae
authors.initials: S
authors.lastname: Maeda
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Hama
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Miyamoto
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Mori
authors.affiliation: Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Osaka, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Doki
authors.affiliation: Department of Hepato-Biliary-Pancreatic Surgery, National Hospital Organization Osaka National Hospital, Osaka, Japan. Electronic address: nakamori@onh.go.jp.
authors.forename: Shoji
authors.initials: S
authors.lastname: Nakamori
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000473:pathology*
keywords: Lymph node; Pancreatic ductal carcinoma; Survival analysis