According to the ASCO and ESMO clinical practice guidelines, the risk of HF increased with high-dose anthracyclines (doxorubicin ≥250 mg/m2) or lower-dose anthracyclines (doxorubicin <250 mg/m2) combined with anti-HER2 therapy (trastuzumab) [13,14]. The gene discussed is ERBB2; the disease is hydrops fetalis.