Quantitative assessment of HER2 amplification in HER2-positive breast cancer: its association with clinical outcomes

摘要: Human epidermal growth factor receptor 2 (HER2) is an effective therapeutic target in breast cancer. However, not all patients benefit from trastuzumab-based therapy. We aimed to investigate whether with different levels of HER2 amplification would experience clinical outcomes chemotherapy. quantified the gene copy number (GCN) and HER2/centromere chromosome probe 17 (CEP17) ratio 291 cancer confirmed by immunohistochemistry fluorescence situ hybridization. The optimal cutoff points for GCN HER2/CEP17 ratios distinguishing positive results were determined receiver operating characteristic (ROC) curve analyses. ROC analysis identified as 11.5 6.5 (P = 0.039 P = 0.012), respectively. DFS <11.5 was significantly longer than ≥11.5 (P = 0.015) according Kaplan–Meier survival curves analysis. Similarly, <6.5 had a those ≥6.5 (P = 0.013). Moreover, cluster showed worse non-cluster (P = 0.041). This study demonstrated significant association between level time relatively large cohort HER2-positive undergoing Further investigations more precise quantitative measurements larger cohorts are required define this threshold.