More recently, biomarkers that have been used to enrich or predict for sensitivity to a targeted agent include BRCA1 and BRCA2 mutations to the PARP inhibitor olaparib [32]-[35]; EML4-ALK fusions to the ALK/MET inhibitor crizotinib [5]; V600E BRAF mutation to the BRAF inhibitor vemurafenib [36]; EGFR wild-type metastatic colorectal cancer to the EGFR-targeted antibodies panitumumab [37] and cetuximab [38]; and EGFR mutant advanced non-small cell lung cancer (NSCLC) to the small molecule inhibitors gefitinib [39] and erlotinib [40],[41]. This evidence concerns the gene ALK and metastatic colorectal cancer.