Best exemplified in lung cancer, multiple biomarker-defined tumours [e.g. Programmed Death Ligand - 1 (PD-L1), Epidermal Growth Factor Receptor (EGFR), Anaplastic Lymphoma Kinase (ALK) mutations, among others] show strong evidence showing superior clinical outcomes (e.g. longer overall and progression free survival), while avoiding the toxicities of cytotoxic chemotherapy [13]. The gene discussed is ALK; the disease is lung cancer.