For instance, in a small prospective cohort of women with early-stage breast cancer, women in the highest versus lowest quartile of fasting insulin had adjusted hazard ratios of 2.1 (95% CI, 1.2 to 3.6) for disease recurrence and 3.3 (95% CI, 1.5 to 7.0) for mortality (25). This evidence concerns the gene INS and breast cancer.