title: The number and ratio of positive lymph nodes affect pancreatic cancer patient survival after neoadjuvant therapy and pancreaticoduodenectomy.
abstract: OBJECTIVE
  This study is to examine the significance of the number and ratio of positive nodes in post-neoadjuvant therapy pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).
  
  
  RESULTS
  Our study population consisted of 398 consecutive PDAC patients, who completed neoadjuvant therapy and PD between 1999 and 2012. Lymph node status was classified as ypN0 (node-negative), ypN1 (1-2 positive nodes) and ypN2 (≥3 positive nodes) and correlated with disease-free survival (DFS) and overall survival (OS). The ypN0, ypN1 and ypN2 was present in 183 (46.0%), 117 (29.4%) and 98 (24.6%) patients, respectively. Additionally, 162 (40.7%) had a lymph node ratio (LNR) ≤0.19 and 53 (13.3%) had a LNR >0.19. Patients with ypN1 disease had shorter DFS and OS than those with ypN0 disease, but better DFS and OS than those with ypN2 disease (P < 0.05). Similarly, patients with a LNR ≤ 0.19 had better DFS and OS than those with a LNR > 0.19 (P < 0.001). In multivariate analysis, both the number of positive nodes and LNR were independent prognostic factors for DFS and OS.
  
  
  CONCLUSIONS
  Subclassification of post-therapy node-positive group into ypN1 (1-2 positive nodes) and ypN2 (≥3 positive nodes) should be incorporated into the American Joint Committee on Cancer (AJCC) staging of PDAC patients.
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Laurice K
authors.initials: LK
authors.lastname: Fischer
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Matthew H
authors.initials: MH
authors.lastname: Katz
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Sun M
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Gauri R
authors.initials: GR
authors.lastname: Varadhachary
authors.affiliation: Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wolff
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jeffrey E
authors.initials: JE
authors.lastname: Lee
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.|Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Anirban
authors.initials: A
authors.lastname: Maitra
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Christina L
authors.initials: CL
authors.lastname: Roland
authors.affiliation: Department of Surgical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jason B
authors.initials: JB
authors.lastname: Fleming
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Jeannelyn
authors.initials: J
authors.lastname: Estrella
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Asif
authors.initials: A
authors.lastname: Rashid
authors.affiliation: Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.|Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
authors.forename: Huamin
authors.initials: H
authors.lastname: Wang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000145:classification* / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D010179:Pancreas / Q000473:pathology / Q000601:surgery; D010190:Pancreatic Neoplasms / Q000145:classification* / Q000175:diagnosis / Q000473:pathology / Q000601:surgery; D016577:Pancreaticoduodenectomy; D011379:Prognosis
keywords: lymph node ratio; number of positive nodes; pancreatic cancer; prognosis; survival