Out of all the T4 patients included in this study, improved survival was observed in cases which were HR+/HER2+, non-black or white with an early-stage tumor stage, and lower tumor grade (Table 2). HR+/HER2+ subtype was significantly associated with a better BCSS (HR: 0.557, 95% CI: 0.349–0.890; P = 0.014) and HR−/HER2- subtype with a poorer BCSS (HR: 2.819, 95% CI: 2.082–3.818; P < 0.001), while BCSS were identical for HR−/HER2+ subtype (HR: 1.272, 95% CI: 0.880–1.837; P = 0.200) as per the multivariate analysis using HR+/HER2- subtype as reference. The gene discussed is ERBB2; the disease is neoplasm.