Next generation sike.

Here’s another reason to retain a healthy dose of skepticism when it comes to genome-guided cancer therapy. Multiple reports now describe deceiving findings when tumors undergo next-generation sequencing (NGS). This can be chalked up to something called clonal hematopoiesis. Basically, hematopoietic precursors acquire advantageous mutations that allow for clonal expansion. It’s a rather benign process, really, except we don’t usually control for it during NGS. In this first report of lung adenocarcinoma, the majority of JAK2 mutations and all of the rare KRAS mutations were actually from peripheral blood cells and not tumor cells. The second report is a huge analysis of the MSKCC-IMPACT tumor sequencing platform. Overall, 5% of detected mutations were actually attributable to clonal hematopoiesis with 3% receiving a targeted therapy based on these misleading results. TBL: When reading a tumor sequencing report, always ask if it was tested against a peripheral blood cell control, especially if selecting a therapy based on the results. | Hu, Clin Cancer Res 2018 | Ptashkin, JAMA Oncol 2018