VacA seropositivity is not associated with the development of gastric cancer in a Japanese population

Objectives Infection with Helicobacter pylori strains producing vacuolating cytotoxin (VacA) is associated with enhanced gastric mucosal damage and th e development of gastric mucosal atrophy, The aim of this study was to inve stigate whether VacA seropositivity is associated with increasing risk of g astric cancer in Japanese populations which have much higher incidence of g astric cancer than Western populations. Methods Serum sample was collected from 81 patients with gastric cancer and 81 sex- and age-matched endoscopically evaluated control subjects. Histolo gically, 62 cancers were of the intestinal type and 76 were early gastric c ancer. H. pylori and VacA IgG antibodies were assayed by Western blotting u sing Chiron Diagnostics' Recombinant Immunoblot Assay (RIBA(a)). Results VacA seropositivity was 68% (55/81) in patients with gastric cancer and 70% (57/81) in controls. The odds ratio for the risk of gastric cancer in VacA seropositives was 0.89 (95% CI 0.46-1.74). In H. pylori seropositi ve patients and their control subjects (matched H. pylori-positive controls ), VacA seropositivity was the same 80.6% (50/62). The odds ratio for the r isk of gastric cancer in H. pylori-positive patients if VacA seropositive w as 1.00 (95% CI 0.41 - 2.44). The mean relative intensity of VacA antibody titre was 3.01 +/- 0.18 in the 55 VacA seropositive cancer patients and 3.0 9 +/- 0.17 in the 57 VacA seropositive control subjects (difference not sig nificant). Conclusion These results suggest that VacA seropositivity is not associated with increasing risk of gastric cancer in Japanese populations. fur J Gast roenterol Hepatol 11:887-890 (C) 1999 Lippincott Williams & Wilkins.