EGFR and breast cancer: Compared with other subtypes of breast cancer, EGFR expression, gene amplification and mutations are more frequently identified and associated with poor prognosis in TNBCs.42, 68, 69 For example, activating mutations in the EGFR gene (exon19 deletion and L858R and T790M mutations) are present in the tumors of TNBC patients.68, 70 Therefore, EGFR may also be a therapeutic target in TNBCs.