We further investigated the relationship between HER2 targeted therapy efficacy and IGF-1 interacted with obesity (Figure S2), and found that only in patients with BMI <24.0 kg/m2 receiving adjuvant targeted therapy, those with higher expression of IGF-1 had a significant superior OS than those with lower IGF-1 (Log-rank P < 0.001). The gene discussed is ERBB2; the disease is obesity due to melanocortin 4 receptor deficiency.