Serum Helicobacter pylori IgG and IgA levels in patients with gastric cancer.

The association between Helicobacter pylori and gastric cancer has been debated in the last decade and evidence for such a causal relationship has been claimed. This study aimed to detect the seroprevalence of Helicobacter pylori in patients with gastric cancer and compare it to the other cancer patients. In addition, the value of IgG and IgA in Helicobacter pylori detection was compared in patients with gastric cancer. Consecutive gastric and other cancer patients treated between 1999-2001 were prospectively studied. Serum Helicobacter pylori IgG and IgA levels were determined. Serological tests revealed IgA and IgG positivity as 53.9% and 50.9%, respectively, while 74.5% had positive results for either IgA or IgG. Serum IgA positivity was significantly higher in gastric cancer group compared to control group (p=0.02). In contrast, serum IgG positivity did not show a significant difference in both groups and either IgG or IgA seropositivity was significantly higher in patients with gastric cancer compared to control patients (p=0.04). This study revealed a higher seroprevalence of Helicobacter pylori in gastric cancer patients and IgA was a better predictor of Helicobacter pylori seropositivity in gastric cancer patients.