ALK and non-small cell lung carcinoma: A recent study demonstrated resistance prediction to ALK-inhibitors in NSCLC patients.751 Another study found that an increase in ctDNA levels at the start or during treatment with EGFR inhibitors was associated with resistance and might be used to predict response to therapy in the future.752 We found no papers on early prediction of resistance for other RTK inhibitor classes, highlighting the need for additional study in this field.