Atlas of Differential Diagnosis

Cytology is a unique subspecialty in anatomic pathology, and plays a critical role in the diagnosis of a variety of benign and malignant lesions by using minimally invasive procedures, such as fine needle aspiration, brushing, washing and lavage. Cytology not only provides an accurate diagnosis of the lesion based on the cytomorphological evaluation at cellular level, but also provides material for molecular characterization of a tumor for targeted therapy. In the era of personalized medicine, cytology has continued to grow and evolve as an important diagnostic tool. For example, some types of procedures are routinely used, diagnostic criteria have become more refined, and certain terminology has been changed based on current WHO classifications. Therefore, it is necessary to update our knowledge and terminology in cytology.