Since the presence of CD44+ CTC clusters is correlated with a poor prognosis in patients with breast cancer 10, we anticipate better therapeutic effects of EGFR inhibition in patients with CD44+EGFR+ CTC clusters, which might serve as a new biomarker to predict the TNBC patient's response to EGFR-targeted treatment. The gene discussed is EGFR; the disease is breast carcinoma.