Cytopathology meets basic science

FNA cytology is now a first‐line diagnostic procedure in many nonneoplastic and neoplastic settings worldwide. Because it is easy to use and cost‐effective, FNA also has become an essential tool in experimental pathology as an alternative to open biopsies and mouse necropsies, and as a means to sample human tumor mouse xenografts as well as mouse models of various types of human tumors. Cytopathologists were instrumental in translating FNA from the clinical setting to the laboratory. They encouraged investigators to handle experimental specimens using the sampling and processing procedures used in the cytology clinic. Today, this integrated approach is being developed even further, particularly in the field of cancer drug development. Indeed, with the widespread use of routine cytological samples to study molecular targeted therapies, cytopathologists are becoming increasingly familiar with the modern tools of genomics, and consequently interactions between cytopathologists and basic scientists have become more effective. Thus, from the simple detection of therapy‐mediated protein changes in target signaling pathways,1, 2 the application of next‐generation sequencing (NGS) to mouse FNA extends the contribution of modern cytopathology to genomic biomarkers.