In the TNBC population, the frequency of ERBB2-low expression has been estimated from 21.0% of the patients in our study to 35.0% in previous reports.14,15 We did not notice any difference in tumor grade or the number or type of metastases, whereas de novo metastatic disease was also more frequent in the ERBB2-low group. This evidence concerns the gene ERBB2 and metastatic neoplasm.