We also demonstrated that high pre-NAC STIL represents a strong predictive marker for pCR.<h4>Conclusion</h4>This study reveals the role of TIL as a predictive biomarker in breast cancer not only for the well-established TNBC (triple negative breast cancer) and HER2+ (Her2 overexpressed) subtypes but also in Luminal A and B molecular subtypes. The gene discussed is ERBB2; the disease is breast carcinoma.