ALK and non-small cell lung carcinoma: The treatment of advanced stage NSCLC has been transformed in recent years by the identification of biomarkers, such as EGFR sensitizing and resistance mutations, ALK and ROS1 rearrangements, PD-L1 expression and tumour mutational burden assessment, allowing clinicians to tailor therapy using tyrosine kinase inhibitors and immunotherapeutic and chemotherapy agents [1,5,24,25].