ERBB2 and neoplasm: Previous studies (Issa-Nummer et al. 2013; Ono et al. 2012; Solinas et al. 2017) have demonstrated that high stromal tumor-infiltrating lymphocytes (sTILs) correlate with a higher likelihood of achieving pCR during NAC in BC across molecular subtypes, with improved DFS in HER2-enriched and TNBC patients, but not in luminalB/HER2- cases.