Gastric cancer shows a strong male predominance, and
sex steroid hormones have been hypothesized to explain this sex disparity. Previous studies examining the associations between
sex hormones and
sex hormone binding globulin (SHBG) and risk of
gastric cancer come primarily from western populations and additional studies in diverse populations will help us better understand the association. We performed a nested case-control study in Linxian Nutrition Intervention Trials cohorts to evaluate the associations among Chinese men, where we had sufficient cases to perform a well-powered study. Using radioimmunoassays and immunoassays, we quantitated
androgens,
estrogens, and SHBG in baseline serum from 328 men that developed noncardia
gastric cancer and matched controls. We used multivariable unconditional logistic regression to calculate
ORs and 95% confidence intervals (CI) and explored interactions with body mass index (BMI), age, alcohol drinking, smoking, and follow-up time. Subjects with SHBG in the highest quartile, as compared with those in the lowest quartile, had a significantly increased risk of
gastric cancer (OR = 1.87; 95% CI, 1.01-3.44). We found some evidence for associations of
sex steroid hormones in men with lower BMI. Our study found a novel association suggesting that higher serum concentrations of SHBG may be associated with risk of
gastric cancer in men. We found no overall associations with
sex hormones themselves, but future studies should expand the scope of these studies to include women and further explore whether BMI modifies a potential association. PREVENTION RELEVANCE: It was the first study to investigate the association of
gastric cancer with prediagnostic
sex steroid hormones and SHBG in an Asian male population. Although there were no overall associations for
sex steroid hormone concentrations, higher concentrations of SHBG was associated with increased risk of noncardia
gastric cancer.