Fig. 2.

Kaplan-Meier analysis-based estimation of probabilities of PFS in metastatic breast cancer patients in accordance with the modification of HER2 copy numbers during HER2-targeted therapy (constantly positive group: the patients whose HER2 copy numbers remained positive after 6 weeks of HER2-targeted treatment; descended to negative group: the patients whose HER2 copy numbers descended to the level below amplification after 6 weeks of HER2-targeted treatment).