LEP and breast cancer: Leptin levels were positively correlated with BMI in both patients with BC (r = 0.52, P < .001) and control patients (r = 0.55, P < .001) in both racial groups; however, a slightly stronger association was observed in Black patients with BC (r = 0.48, P < .001) or Black controls without BC (r = 0.56, P < .001) compared with their White counterparts (r = 0.46, P = .001 for both groups) (eFigure in Supplement 1).