Chapter 5: Cytology
Cytology is the microscopic examination of unfixed solid or fluid samples collected from any body site using a variety of methods. Cytology is particularly useful for assessing body fluids, lymph nodes, airways, accessible masses, and bone marrow in the live animal. Relative to histopathology, cytology is fast, inexpensive, and minimally invasive. In canine and feline skin masses, the cytologic diagnosis correlates with histopathology in 90-97% of cases. However, for certain lesions, histopathology is required to make a definitive diagnosis, for example, when cells do not exfoliate well, when architecture is particularly important, when additional tests, such as immunohistochemistry, are required, and when the cytology sample is not representative of the lesion.
Microscopic examination of unfixed solid tissue or fluid samples.
Organ responsible for production of hemopoietic cells; found in the medullary cavity, especially the ends of long bones (e.g. femur) and flat bones (e.g. the pelvis, sternum.)
To peel off; used to describe cytologic samples, e.g. tumors such as adenocarcinomas tend to exfoliate well and aspirates from them are often highly cellular.
Technique by which cells in tissue (e.g. poorly differentiated neoplastic cells) can be identified based on cell surface markers.
