PTTG1 and breast cancer: In comparison with the prognostic values of securin and Ki-67, univariate Cox's survival analysis for securin indicated a 2.9-fold (P=0.006, 95% CI 1.3–6.0) and for Ki-67 a 2.4-fold risk of breast cancer death (P=0.004, 95% CI 1.3–4.5).