Also, no mutations were detected for other described breast cancer‐associated genes (e.g., RAD51, RAD50, p27, ESR1/2, ERBB2, ERBB3, AKT1, CCDN1, FGFR1, MYC, and RB1) in any of the tissues or the CTC cell line. The gene discussed is ERBB2; the disease is breast cancer.