Bi-directional Sanger sequencing of ALK is performed using PCR primers designed to target hotspot mutations in exons 23 and 25.
ALK gene translocations are a well-known cause of gene deregulation and target of ALK inhibitors in non-small cell lung carcinoma (NSCLC). However, point mutations in the ALK tyrosine kinase domain, such as those detected by this test, are reported in patients who develop resistance to this therapy. Mutation analysis can help predict sensitivity or resistance to first and second generation inhibitors such as crizotinib, alectinib, and ceritinib. Reported mutations include F1174V, F1174L, L1196M, and G1202R.
- FFPE tissue: Paraffin block is preferred. Alternatively, send 1 H&E slide plus 5-10 unstained slides cut at 5 or more microns. Please use positively-charged slides and 10% NBF fixative. Do not use zinc fixatives.
Use cold pack for transport, making sure cold pack is not in direct contact with specimen. All slides can be packed at room temperature.