White Blood Cell Count and Risk of Gastric Cancer Incidence in a General Japanese Population
Menée en population japonaise sur la période 1988 à 2007, cette étude analyse l'association entre le nombre de globules blancs et le risque de cancer de l'estomac, en fonction de la présence d'une infection par Helicobacter pylori
The authors examined the association between white blood cell (WBC) count and the development of gastric cancer in a 19-year follow-up study of 2,558 Japanese subjects aged ≥40 years (1988–2007). The subjects were stratified into 4 groups according to baseline WBC quartile (≤4.4, 4.5–5.2, 5.3–6.3, or ≥6.4 × 103 cells/μL). During follow-up, 128 subjects developed gastric cancer. The age- and sex-adjusted incidence of gastric cancer increased linearly with higher WBC level: 1.7, 2.6, 3.9, and 5.4 per 1,000 person-years, respectively, for the 4 quartile groups (P for trend < 0.01). The risk of gastric cancer was 2.22-fold (95% confidence interval: 1.19, 4.14) higher in the highest WBC quartile group than in the lowest group after adjustment for confounding factors. With respect to Helicobacter pylori infection status, H. pylori-seropositive subjects in the highest WBC quartile group showed a significantly greater risk of gastric cancer than those in the lower 3 quartile groups, whereas such an association was not observed in H. pylori-seronegative subjects. There was no evidence of heterogeneity in the association (P for heterogeneity = 0.65). The study findings suggest that higher WBC levels are a risk factor for gastric cancer, especially in subjects with H. pylori infection.