Based on this analysis, there were no relationships between pN0 and age (< 45 vs. ≥45), menopausal status (premenopausal vs. postmenopausal), tumor location (right breast vs. left breast), tumor location (upper-inner, upper-outer, lower-inner, lower-outer, retroareolar), or baseline Ki-67 value (continuous). This evidence concerns the gene MKI67 and neoplasm.