Cytopathology in the diagnosis,treatment and management of malignant respiratory disease

Lung carcinomas are almost always diagnosed using small samples of cellular material. Diagnostic cytopathology has a major role and, with efficient and thoughtful processing and examination of fine needle aspiration or fluid specimens, it is possible to accurately diagnose and perform a full range of predictive testing. This short piece begins by placing cytopathology within an overall umbrella of cellular pathology and briefly describes recent developments in lung cancer diagnosis and treatment. Cytopathological features of the main relevant tumour types and their differential diagnoses are discussed together with their appearance in commonly encountered specimen types such as those from endobronchial ultrasound. There are suggestions for efficient workflow and illustrations of diagnostic pitfalls. Although some trainees are wary of cytopathology, there is no magic (good or bad) involved and any time spent acquiring a facility with interpretation of these specimens as well as their formalin-fixed counterparts will enhance diagnostic skill and, ultimately, patient care.