Firstly, in ALK fusion–positive ILS31007, we confirmed that the NAT specimens did not include any tumor cells (Additional file 11: Figure S7) and that the EML4 mRNA levels at exon1/2, 2/3, 5/6, or 6/7 in NAT were almost the same as those in the tumor tissues (Fig. 3c and Additional file 12: Figure S8). Here, ALK is linked to neoplasm.