In contrast, among women with T2DM and breast cancer diagnosed between the ages of 50 and 69 years, the lowest crude 3-year breast cancer specific survival was among those with HER2-enriched tumours was about 8% lower compared to 78.2 for TNBC tumours and 93.8 for luminal A tumours. The gene discussed is ERBB2; the disease is type 2 diabetes mellitus.