title: Preoperative Helicobacter pylori Infection is Associated with Increased Survival After Resection of Gastric Adenocarcinoma.
abstract: BACKGROUND
  Limited data exist on the prognosis of preoperative Helicobacter pylori (H. pylori) infection in gastric adenocarcinoma (GAC).
  
  
  METHODS
  Patients who underwent curative-intent resection for GAC from 2000 to 2012 at seven academic institutions comprising the United States Gastric Cancer Collaborative were included in the study. The primary end points of the study were overall survival (OS), recurrence-free survival (RFS), and disease-specific survival (DSS).
  
  
  RESULTS
  Of 559 patients, 104 (18.6 %) who tested positive for H. pylori were younger (62.1 vs 65.1 years; p = 0.041), had a higher frequency of distal tumors (82.7 vs 71.9 %; p = 0.033), and had higher rates of adjuvant radiation therapy (47.0 vs 34.9 %; p = 0.032). There were no differences in American Society of Anesthesiology (ASA) class, margin status, grade, perineural invasion, lymphovascular invasion, nodal metastases, or tumor-node-metastasis (TNM) stage. H. pylori positivity was associated with longer OS (84.3 vs 44.2 months; p = 0.008) for all patients. This relationship with OS persisted in the multivariable analysis (HR 0.54; 95 % CI 0.30-0.99; p = 0.046). H. pylori was not associated with RFS or DSS in all patients. In the stage 3 patients, H. pylori was associated with longer OS (44.5 vs 24.7 months; p = 0.018), a trend of longer RFS (31.4 vs 21.6 months; p = 0.232), and longer DSS (44.8 vs 27.2 months; p = 0.034).
  
  
  CONCLUSIONS
  Patients with and without preoperative H. pylori infection had few differences in adverse pathologic features at the time of gastric adenocarcinoma resection. Despite similar disease presentations, preoperative H. pylori infection was independently associated with improved OS. Further studies examining the interaction between H. pylori and tumor immunology and genetics are merited.
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Postlewait
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
authors.forename: Malcolm H
authors.initials: MH
authors.lastname: Squires
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Kooby
authors.affiliation: Department of Surgery, Stanford University Medical Center, Stanford, CA, USA.
authors.forename: George A
authors.initials: GA
authors.lastname: Poultsides
authors.affiliation: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Sharon M
authors.initials: SM
authors.lastname: Weber
authors.affiliation: Division of Surgical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Bloomston
authors.affiliation: Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Fields
authors.affiliation: Department of Surgery, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Pawlik
authors.affiliation: Department of Surgery, Wake Forest University, Winston-Salem, NC, USA.
authors.forename: Konstantinos I
authors.initials: KI
authors.lastname: Votanopoulos
authors.affiliation: Division of Surgical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA.
authors.forename: Carl R
authors.initials: CR
authors.lastname: Schmidt
authors.affiliation: Department of Surgery, The Johns Hopkins Hospital, Baltimore, MD, USA.
authors.forename: Aslam
authors.initials: A
authors.lastname: Ejaz
authors.affiliation: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Alexandra W
authors.initials: AW
authors.lastname: Acher
authors.affiliation: Department of Surgery, Stanford University Medical Center, Stanford, CA, USA.
authors.forename: David J
authors.initials: DJ
authors.lastname: Worhunsky
authors.affiliation: Division of Surgical Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA.
authors.forename: Neil
authors.initials: N
authors.lastname: Saunders
authors.affiliation: Department of Surgery, Wake Forest University, Winston-Salem, NC, USA.
authors.forename: Douglas
authors.initials: D
authors.lastname: Swords
authors.affiliation: Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Linda X
authors.initials: LX
authors.lastname: Jin
authors.affiliation: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Clifford S
authors.initials: CS
authors.lastname: Cho
authors.affiliation: Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
authors.forename: Emily R
authors.initials: ER
authors.lastname: Winslow
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Cardona
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA.
authors.forename: Charles A
authors.initials: CA
authors.lastname: Staley
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Winship Cancer Institute, Emory University, Atlanta, GA, USA. smaithe@emory.edu.
authors.forename: Shishir K
authors.initials: SK
authors.lastname: Maithel
mesh_terms: D000230:Adenocarcinoma / Q000382:microbiology / Q000401:mortality* / Q000601:surgery; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D005743:Gastrectomy / Q000401:mortality*; D016481:Helicobacter Infections / Q000150:complications / Q000382:microbiology / Q000401:mortality*; D016480:Helicobacter pylori; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D011300:Preoperative Care; D011379:Prognosis; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000382:microbiology / Q000401:mortality* / Q000601:surgery; D015996:Survival Rate