Posted October 1, 2022 by Anusha ‐ 5 min read
Cytology is a common method for determining a diagnosis in the medical world. Cytology tests use small amounts of bodily tissue or fluid in order to examine certain types of cells.
What is cytology?
Cytology (also known as cytopathology) involves examining cells from bodily tissues or fluids to determine a diagnosis.
A certain kind of physician, called a pathologist, will look at the cells in the tissue sample under a microscope and look for characteristics or abnormalities in the cells.
Since cytology only examines cells, which are so tiny, pathologists only need a very small sample of tissue to do a cytology test.
Types of Cytology
There are two main kinds, or branches, of cytology:
Healthcare providers can use cytology tests for almost all areas of your body. Some common types of cytology tests include:
Lymph node cytology.
Uses of Cytology
Healthcare providers and pathologists most commonly use cytology to diagnose or screen for cancer.
A healthcare provider only uses a diagnostic test for a person if they have signs or symptoms that suggest they might have a certain disease or infection.
A diagnostic test, such as a cytology test, determines if abnormal cells are present.
If so, the test accurately classifies the disease.
A healthcare provider uses screening tests to see if a person could have a certain disease, such as cancer, even before they experience symptoms.
A popular type of cytology screening test is a Pap smear.
Other uses for cytology tests include:
To diagnose infectious diseases.
To diagnose inflammatory conditions.
To examine thyroid lesions.
To diagnose diseases involving certain body cavities, such as the space that’s between two thin membranes that line and surround your lungs (pleural cavity).
Process of Cytology
Each cytology test is slightly different depending on what kind of cells are being tested and if the sample is tissue or fluid. In general, there are four steps to a cytology test including:
Collecting the sample cells.
Processing the sample cells.
Examining the sample cells.
Sharing the results.
Collecting the sample cells
Your healthcare provider collects the sample of cells from your body that they need a pathologist to examine. Some of the ways a provider can collect cytology test samples include:
Brushing or scraping tissue from the surface of a part of your body.
Collecting fluid or discharge samples from your body, such as a pee sample.
Using fine-needle aspiration to draw a fluid sample from an area in your body.
Processing the sample cells
For some types of cytology tests that involve tissue samples, the healthcare provider who took the sample smears or spreads it on glass microscope slides.
These slides are known as smears.
They then send the smears to a pathology laboratory.
If the cytology test involves bodily fluid, the healthcare provider most likely won’t be able to use smears since the sample is too diluted (there are only a few cells in the fluid).
They’ll most likely send the sample to a pathology lab in a small container.
Once a cytology sample arrives at the laboratory, a pathologist or lab technician dips the smears in certain stains (colored dyes) depending on what kind of sample it is.
The stains help make the cells easier to see and examine under a microscope.
If the cytology sample is a fluid, a pathologist or lab technician may use a machine called a centrifuge to separate the cells they want to examine from the fluid.
A centrifuge separates certain cells from fluid by spinning the sample very quickly.
The pathologist then puts the cells on smears and may stain them.
Examining the sample cells
After a pathologist or lab technician processes and stains the cytology samples, they examine the cells under a microscope, looking for abnormal cells.
If they find abnormal cells, they mark them on the slides with a special pen.
A pathologist then makes a diagnosis based on the cells and puts together a report.
Sharing the results
After they put together a report, the pathologist will send it to your healthcare provider. Your provider will go over the results with you and determine the next steps.
Benefits of Cytology
Cytology tests have many benefits due to the small amount of tissue or fluid sample that is needed for the test. Compared to a tissue biopsy, which healthcare providers also use to determine a diagnosis, a cytology test:
Is less invasive.
Causes less discomfort and pain.
Is less likely to cause complications.
What type of results do you get from a cytology test?
The type of results you get from a cytology test depends on what type of test it is and what part of your body was sampled.
A pathologist’s report for a cytology test may include:
If they found abnormal cells or not.
If they found abnormal cells, what type of disease, infection or cancer is present in the sample.
If it’s cancer, grading the cancer. While identifying the type of cancer cell in the sample, pathologists also decide how closely the cancer cells look like the normal cells or tissues. This is called the grade of the cancer.
If further testing is needed, such as a biopsy.