title: Prognostic Value of Perineural Invasion in Esophageal and Esophagogastric Junction Carcinoma: A Meta-Analysis.
abstract: OBJECTIVE
  Here we aimed to clarify the prognostic significance of perineural invasion (PNI) in esophageal and esophagogastric junction (EGJ) carcinoma.
  
  
  METHODS
  A comprehensive literature search for relevant reports published up to July 2015 was performed using Pubmed and Embase databases. The pooled HR and 95% CI for overall survival (OS) and disease-free survival (DFS) were used to assess the prognostic value. The association of PNI with pathological characteristics was evaluated by OR and 95% CI.
  
  
  RESULTS
  A total of 13 cohorts were retrieved, covering 2770 patients treated by surgery. The cumulative analysis revealed a statistical correlation between PNI and poor OS (HR = 1.76, 95% CI: 1.54-2.20, and P < 0.00001), as well as poor DFS (HR = 1.96, 95% CI: 1.42-2.71, and P < 0.001). Moreover, analysis of 1475 patients showed improved PNI in T3 + T4 (OR = 0.39, 95% CI: 0.21-0.70, and P = 0.002), N+ (OR = 0.52, 95% CI: 0.40-0.69, and P < 0.00001), and G3 + G4 (OR = 0.66, 95% CI: 0.48-0.90, and P = 0.008) patients compared with T1 + T2, N-, and G1 + G2 ones, respectively. No significant heterogeneity was found between the studies.
  
  
  CONCLUSIONS
  PNI is an adverse prognostic biomarker in esophageal and EGJ carcinoma. Moreover, PNI implies advanced T, N stage and poor cell differentiation.
authors.affiliation: Department of Oncology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China.
authors.forename: Aiqin
authors.initials: A
authors.lastname: Gao
authors.affiliation: Department of Oncology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China; Department of Radiotherapy, Shandong Cancer Hospital, Jinan 250117, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Wang
authors.affiliation: School of Medicine, Shandong University, Jinan 250012, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Medical Insurance, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Li
authors.affiliation: School of Medicine, Shandong University, Jinan 250012, China.
authors.forename: Yali
authors.initials: Y
authors.lastname: Han
authors.affiliation: Endoscopy Center, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China.
authors.forename: Xiaoxia
authors.identifier: 0000-0003-1190-7583
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Oncology, Jinan Central Hospital Affiliated to Shandong University, Jinan 250013, China.
authors.forename: Yuping
authors.initials: Y
authors.lastname: Sun
mesh_terms: D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000401:mortality / Q000473:pathology*; D004943:Esophagogastric Junction / Q000473:pathology*; D005770:Gastrointestinal Neoplasms / Q000401:mortality / Q000473:pathology*; D006801:Humans; D009361:Neoplasm Invasiveness; D010525:Peripheral Nerves / Q000473:pathology*; D011379:Prognosis; D016019:Survival Analysis