ALK and neoplasm: On day 21, the mean xenograft tumor volume of the CTC15035EML4–ALK control group grew from 176.65 ± 24.77 to 1764.72 ± 34.43 mm3, whereas under 50 mg/kg crizotinib treatment the xenograft tumors shrank from 176.18 ± 20.00 to 128.26 ± 34.43 mm3 (P < 0.001), with a TGI% of 103.2% and a T/C% of − 3.02% on day 21 (Fig. 4a).