Antibody against Helicobacter pylori CagA and VacA and the risk for gastric cancer.

AIM

Helicobacter pylori is associated with gastric cancer. Our aim was to investigate whether CagA or VacA seropositivity provides additional risk for gastric cancer.

METHODS

Sera from 110 gastric cancer patients were sex and aged matched with asymptomatic controls. H pylori status was determined by IgG enzyme immunoassay (HM-CAP EIA); CagA status was assessed by enzyme linked immunosorbent assay (ELISA) (OraVax) and immunoblotting (Chiron), and VacA status by immunoblotting using recombinant proteins as antigens.

RESULTS

H pylori infection was associated with an increased risk of gastric cancer (odds ratio (OR) = 2.19, 95% confidence interval 1.17 to 4.1). Subgroup analysis showed a significant association with intestinal type (OR = 2.94, 1.35 to 6.41), distal type (OR = 2.97, 1.39 to 6.33), early gastric cancer (OR = 3.74, 1.54 to 9.06), and age < or = 55 years (OR = 8.33, 2.04 to 34.08), but not with diffuse type (OR = 0.83), proximal type (OR = 1.0), advanced gastric cancer (OR = 1.13), or age > 55 years (OR = 1.40). Serum CagA IgG and VacA antibody positivity was present in similar proportions in patients with and without cancer, with no significant differences in histological classification, clinical stage, or location (p > 0.3).

CONCLUSIONS

H pylori infection causes chronic gastritis and is associated with the development of gastric cancer. Neither CagA nor VacA seropositivity added additional information or stratification.