In the PURE-01 cohort, TMB≥10 mut/Mb was significantly associated with pCR and downstaging at univariable and multivariable analyse....TMB≥10 was associated with response to pembrolizumab, while HRR GAs with DRFS after NAC. Cases with ERBB2/3 GAs featured higher TMBs but were not associated with response to immunotherapy.