Cytopathology in focus—Predictive markers in cytopathology: programmed death ligand-1

August 2026—Although cytologists and cytopathologists expend considerable effort in screening, risk stratification, diagnosis, staging, and prognostication, clinicians are increasingly demanding ancillary testing that predicts response or resistance to the broad range of therapeutic agents available to them. In advanced-stage non-small cell lung carcinoma, these therapies include tyrosine kinase…