Aim To examine the association between gastric atrophy, Helicobacter pylori and CagA status, and ratio of oesophageal squamous cell carcinoma to oesophageal adenocarcinoma (OSCC:OAC) amongst international heterogeneous populations.

Methods Standardised protocols were used to collect and process questionnaire data and serum samples for PgA and PgC levels and H. pylori and CagA serology. The OSCC:OAC were used to construct appropriate models.

Results There were significant correlations between the OSCC:OAC and both rates of low PgA:PgC ratios and serological markers of H. pylori infection, in males, but not females. A significant correlation between OSCC:OAC and overall CagA-seropositivity was seen in males, but not females, but this was not independently associated with increasing OSCC:OAC.

Conclusions In males, populations with higher rates of gastric atrophy or H. pylori infection have a higher OSCC:OAC. CagA seropositivity rates seem to have no additional effect.