FIGURE 5.

A, Change of fractional abundance of epidermal growth factor receptor (EGFR) mutation in Case A17 is shown. After osimertinib treatment, multiple brain metastasis remained in remission. PET‐CT examination revealed disease progression of left femur bone metastasis. B, Change of fractional abundance of EGFR mutation in Case A19 is shown. After osimertinib treatment, primary lung tumor and other metastasis remained stable with CT examination. MRI examination revealed L5 vertebrae metastasis progression