HR and breast cancer: Thus, Pearson et al. have sequenced 210 samples of advanced breast cancers (including 63% of HR+/HER2- tumors, 12% HER2+ and 17% TNBC), and observed enrichment when compared to primary tumors, for mutations of HER2 (6,2%), AKT1 (7,1%), and NF1 (8,1%).