In addition, a strong relationship was established between poor prognostic indicators and KI-67 expression in this study, where Nigerian women with KI-67 expression were associated with patient diagnosed earlier in life, premenopausal, larger tumour size, lymph node involvement, vascular invasion, exhibited a basal phenotype, and triple negative, lacked hormone receptors, BRCA1, and shorter BCSS compared with British women. The gene discussed is BRCA1; the disease is neoplasm.