A pilot study of Helicobacter pylori infection and risk of laryngopharyngeal cancer.
BACKGROUND
Squamous cell carcinoma of the laryngopharynx has been linked to laryngopharyngeal reflux disease. Helicobacter pylori corpus gastritis decreases gastric acid secretion and provides some protection against complications of gastroesophageal reflux, including adenocarcinoma of the distal esophagus. The aim of this study was to investigate whether H. pylori infection also protects against laryngopharyngeal carcinoma.


METHODS
This was a case-control study comparing patients with histologically confirmed, previously untreated laryngeal or pharyngeal squamous cell carcinomas with cancer-free controls selected from a pool of hospital-based cancer-free controls identified during a similar time period. Each subject completed a self-administered questionnaire that elicited information on age, sex, ethnicity, and tobacco and alcohol consumption. The 120 case subjects were frequency matched to 120 control subjects on age (+/- 5 years), sex, tobacco use, and alcohol use; all subjects were non-Hispanic whites. H. pylori and human papillomavirus type 16 (HPV-16) seropositivity was determined by use of an enzyme-linked immunosorbent assay.


RESULTS
The serologic assay was unsuccessful in one case subject and nine control subjects; therefore, 119 case subjects and 111 control subjects were included in the analysis. The proportion of subjects with anti-H. pylori immunoglobulin G was similar between the two groups (32.8% among cases vs 27.0% among controls; p = .342). Although seropositivity was more common in the patients with laryngeal cancer (39.1%) than in the patients with pharyngeal cancer (28.8%), this difference was neither significant (p = .241) nor associated with a significant risk of laryngeal cancer (adjusted odds ratio, 1.53; 95% confidence interval, 0.69-3.41). H. pylori seropositivity was more common among patients who were HPV-16 seronegative (38.2% vs 22.9%, p = .081), and this was particularly true among patients with laryngeal cancer (47.1% vs 18.2%; p = .089).


CONCLUSIONS
These results do not show that H. pylori infection either protects against or promotes laryngopharyngeal carcinoma. However, segregation analyses suggested that H. pylori may play a role in laryngeal cancers not associated with HPV-16 infection, and further study in this group is warranted.
Department of Gastroenterology--Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, USA.
Zhannat Z
ZZ
Nurgalieva
David Y
DY
Graham
Kristina R
KR
Dahlstrom
Qingyi
Q
Wei
Erich M
EM
Sturgis
D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D002294:Carcinoma, Squamous Cell / Q000097:blood*; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D016481:Helicobacter Infections / Q000097:blood*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007822:Laryngeal Neoplasms / Q000097:blood*; D008297:Male; D008875:Middle Aged; D027383:Papillomaviridae / Q000302:isolation & purification; D030361:Papillomavirus Infections / Q000097:blood; D010610:Pharyngeal Neoplasms / Q000097:blood*; D010865:Pilot Projects; D011795:Surveys and Questionnaires
D000907:Antibodies, Bacterial; D007074:Immunoglobulin G