title: Acid reflux and head and neck cancer risk: A nationwide registry over 13 years.
abstract: OBJECTIVE
  Gastro-esophageal reflux disease (GERD) is a highly prevalent disorder; however, important questions remain regarding the link between GERD and extra-esophageal cancers. This nationwide cohort study investigated the risk of developing head and neck cancers (HNCs) among patients with GERD.
  
  
  METHODS
  Newly diagnosed GERD patients aged ≥20 years without antecedent cancer were included. Case data were obtained from the National Health Insurance Research Database covering period from 1998 to 2010. We compared the standardized incidence ratios (SIRs) of cancer among GERD patients with those of the general population.
  
  
  RESULTS
  A total of 98 cancers were identified among the 39,845 GERD patients in the study, representing 128,361 person-years. The SIR for all cases of cancer was 1.59 (95% CI 1.29-1.93). GERD patients exhibited significantly higher SIRs for oropharyngeal (SIR 3.58, 95% CI 1.85-6.25) and hypopharyngeal (SIR 3.96, 95% CI 2.35-6.26) cancers. Male patients had a significantly higher risk of HNCs (SIR 1.70, 95% CI 1.36-2.10), particularly oropharyngeal (SIR 4.01, 95% CI 2.00-7.17) and hypopharyngeal (SIR 3.91, 95% CI 2.28-6.26) cancers. Following adjustment for age and co-morbidities, the hazard ratio was 9.06 (95% CI 4.70-17.44) for males compared to females.
  
  
  CONCLUSIONS
  There may be a potential association between GERD and risk of HNCs, which however merits further studies to confirm the causal relationship. Our observations indicate a need for careful extra-esophageal examination of patients with acid reflux. Our findings also underline the importance of raising awareness among clinicians regarding the possibility of concurrent HNCs in GERD patients with refractory laryngo-pharyngeal symptoms.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan, ROC; Department of Otolaryngology, National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC; Department of Otolaryngology, Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan, ROC; Department of Otolaryngology-Head and Neck Surgery, National Defense Medical Center, Taipei, Taiwan, ROC. Electronic address: drkuochinlung@gmail.com.
authors.forename: Chin-Lung
authors.initials: CL
authors.lastname: Kuo
authors.affiliation: Division of Nephrology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Medicine, Taipei City Hospital Heping Fuyou Branch, Taipei, Taiwan, ROC.
authors.forename: Yung-Tai
authors.initials: YT
authors.lastname: Chen
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Otolaryngology, National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC; Department of Otolaryngology-Head and Neck Surgery, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: An-Suey
authors.initials: AS
authors.lastname: Shiao
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Department of Otolaryngology, National Yang-Ming University School of Medicine, Taipei, Taiwan, ROC.
authors.forename: Chiang-Feng
authors.initials: CF
authors.lastname: Lien
authors.affiliation: Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan, ROC; Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan, ROC. Electronic address: sjwang@vghtpe.gov.tw.
authors.forename: Shuu-Jiun
authors.initials: SJ
authors.lastname: Wang
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D005260:Female; D005764:Gastroesophageal Reflux / Q000453:epidemiology*; D006258:Head and Neck Neoplasms / Q000453:epidemiology*; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000453:epidemiology; D007822:Laryngeal Neoplasms / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology; D009303:Nasopharyngeal Neoplasms / Q000453:epidemiology; D009669:Nose Neoplasms / Q000453:epidemiology; D009959:Oropharyngeal Neoplasms / Q000453:epidemiology; D016016:Proportional Hazards Models; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D012468:Salivary Gland Neoplasms / Q000453:epidemiology; D012737:Sex Factors; D013624:Taiwan / Q000453:epidemiology
keywords: Gastro-esophageal reflux; Head and neck; Neoplasms; Population-based; Risk factor