Cytopathology is the use of specialist diagnostic techniques to examine individual cells extracted from tissues to determine the cause and nature of a disease. Cell samples may be gathered during routine diagnostic tests, such as bronchoscopy and cystoscopy.
Cytopathology is commonly used to investigate diseases involving a wide range of body sites, often to aid in the diagnosis of cancer but also in the diagnosis of some infectious diseases and other inflammatory conditions. For example, a common application of cytopathology is the Pap smear, a screening tool used to detect precancerous cervical lesions that may lead to cervical cancer.