Background: The genetic determinants of sporadic renal cell cancer (RCC) are largely unknown. Previous studies have suggested associations between the ABO blood group and risk of various cancers, however, its relationship to RCC remains unclear.

Methods: We prospectively evaluated the association between the ABO blood group and risk of RCC in two large independent cohorts of women (the Nurses' Health Study) and men (the Health Professionals Follow-up Study) from 1996 to 2008. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards models with adjustment for other risk factors for RCC including obesity, smoking, and hypertension. All statistical tests were two-sided.

Results: During 12 years of follow-up of 77,242 women and 29,548 men, 163 cases of incident RCC were documented in women and 84 cases in men. After multivariate adjustment, non-O blood group (combined group of A, AB, and B) was associated with a 1.5-fold elevated risk of RCC (95% CI 1.09–2.09) than O blood group in women. In contrast, no significant associations were observed between the ABO blood group and risk of RCC in men. The associations between the ABO blood group and RCC were consistent across strata of known risk factors including obesity, smoking status, and history of hypertension (Pinteraction ≥ .58) in both cohorts.

Conclusion: We show for the first time that non-O blood group is significantly associated with a higher risk of RCC compared with blood group O in women. Further studies that elucidate the biological mechanisms underlying this association are warranted.

Citation Information: Cancer Prev Res 2011;4(10 Suppl):A94.