Cytology Smears in the Era of Molecular Biomarkers in Non–Small Cell Lung Cancer: Doing More With Less

Context.— The rapid advances in targeted therapies in non–small cell lung cancer (NSCLC) make the optimization and implementation of cytology specimens for molecular testing a priority. Up to 70% of patients with NSCLC are diagnosed at advanced stages and tissue biopsies often cannot be taken. Although cytology samples provide high-quality material for molecular testing, molecular cytopathology is not yet well known or widely used. Objective.— To report the many advances in molecular cytopathology and the suitability and utility of cytology samples in molecular and genetic testing of NSCLC. Data Sources.— Data sources comprised published peer-reviewed literature and personal experience of the authors. Conclusions.— Molecular testing can be performed on cytologic specimens, especially on direct smears. Rapid on-site evaluation by cytopathologists has improved the adequacy and the management of cytology samples for molecular testing. Mutational profiling of NSCLC using next-generation sequencing can be perf...