Better Survival of Helicobacter pylori Infected Patients with Early Gastric Cancer Is Related to a Higher Level of Thomsen‐Friedenreich Antigen‐Specific Antibodies

Abstract

The survival of patients with histologically verified gastric carcinoma at stage I (n = 44) and stage II (n = 43) was analysed by the Kaplan‐Meier method depending on H. pylori serological status and a level of IgG and IgM antibody to tumor‐associated Thomson‐Friedenreich antigen (T Ag). In cancer patients at stage I, significantly better survival for H. pylori seropositive patients was observed compared to H. pylori‐seronegative patients (median±SE survival time: 60.0±3.8 mths and 37.0±7.8 mths, respectively; P < 0.0004, log‐rank test). Patients with higher level of T Ag‐specific IgG antibody (strong responders) showed significantly and dramatically better (P < 0.00001) survival rate than weak responders. However, an association of better survival with a higher level of anti‐T antibody level was limited to the H. pylori seropositive patients exclusively (P < 0.00001) with no difference for H. pylori seronegative group of patients. The level of IgM anti‐T Ag antibody was not significantly related to the survival of patients at both stages of the disease, though better survival was noted in H. pylori seropositive IgM strong responders at ~40–60 months of observation. Statistically insignificant associations between survival and H. pylori status or anti‐T antibody levels were also observed in a group of gastric cancer patients at stage II. In summary, the survival of patients with early gastric cancer (stage I) is significantly better in H. pylori seropositive patients, and this phenomenon may be in part explained by up‐regulation of T Ag‐specific IgG immune response in H. pylori infected individuals.