Cytology is the microscopic examination of cells that have been collected from the body. By examining the appearance of these cells, including their number, size, shape, color, internal characteristics, and how they fit together with their neighbors, it is often possible to make a diagnosis of a specific disease process.

Cytology is most often used to diagnose the nature of ‘lumps and bumps’ found on the surface of the body. However, cytology can also be used to evaluate:

  • internal organs, such as the liver, lungs, lymph nodes, and kidneys
  • body fluids, such as urine or joint fluid
  • abnormal accumulations of fluids (called effusions), especially in the chest and abdomen
  • various surfaces of the body, both external and internal (e.g., mouth, eyes, breathing passages, or vagina)

Cytology is often used for preliminary evaluation to establish a working diagnosis and as needed, plan surgery. It is a non-invasive method for gathering preliminary information about certain medical conditions. Little equipment is required and sample collection can often be performed without sedation or anesthesia.


How is the sample collected?

There are several ways to collect the cells depending on where the problem is and what type of tissue is involved.

  • Fine needle aspiration or fine needle biopsy: This technique uses a sterile, fine gauge needle (a needle with a very small diameter) attached to an empty syringe. The needle is inserted into the middle of the tissue or pocket of fluid and the plunger of the syringe is pulled back to create suction and withdraw or aspirate cells from solid tissue, such as a skin lump, or to collect fluid from a site, such as a joint.
More information about fine needle aspirate!
  • Skin scraping. This technique pulls a few cells away from the surface of the skin (often used on flaky, or ulcerated skin).
  • Impression smear. In this technique, a glass microscope slide is pressed firmly on an ulcerated lesion. This allows the surface materials to be collected and examined under a microscope.
  • Cotton-tipped swabs. Cotton-tipped swabs are used to collect discharge and cells from moist skin surfaces such as the eye, nose, mouth, or vagina.
  • Lavage. This technique is used to collect cells from internal surfaces such as the nasal cavity, trachea (windpipe), or lung. Fluid is flushed into the area and then suctioned back out. Cells are collected in the fluid and are examined under the microscope.
More information about cytology!