The high degree of spatial heterogeneity observed for SNVs in druggable target genes is exemplified by the ALK R1275Q mutation only being detected in 2 of 7 locations in the relapse tumour, the BRAF V600E mutation in only 3 of 7 locations and the FGFR1 N557K mutation in only 5 of 7 locations. This evidence concerns the gene ALK and neoplasm.