What is urine cytology?
Cytology is the examination of cells from the body under a microscope. In a urine cytology exam, a doctor looks at cells collected from a urine specimen to see what types of cells are being eliminated from your body in your urine. The test commonly checks for infection, inflammatory disease of the urinary tract, cancer, or precancerous conditions.
It’s important to note that this test doesn’t identify cancer, nor can it completely rule out cancer. Urine cytology is better at finding larger and more aggressive cancers than small, slow growing cancers.
This procedure is different from a biopsy in that it examines individual cells, rather than pieces of tissue containing many cell clusters. The cells for urine cytology are easier to obtain than tissue, causing less discomfort and less risk to the patient. Sometimes a biopsy is necessary after abnormal results from urine cytology to clarify a diagnosis.
Your doctor may order a urine cytology exam if you have any of these symptoms:
- unexplained blood in your urine
- burning during urination
- persistent pain during urination
The test also monitors those who’ve had urinary tract infections or cancer or who are at high risk for bladder cancer. It can also detect a variety of viral diseases.
There are two ways to obtain the cells needed for a cytology exam. Your doctor can collect a sample during a cystoscopy, which is an examination of the inside of the bladder, or you can provide a clean catch urine sample.
A cystoscopy is performed using a cystoscope, a thin tube with a small camera on the end. The procedure takes between 10 and 20 minutes.
Because the urine from your first morning urination remains in your bladder for many hours through the night, the cells may degrade and not be useful for urine cytology. However, this doesn’t mean you should urinate right before the test. In fact, you may need to hold urine in your bladder for a few hours prior to cystoscopy. Be sure to ask your doctor for specific instructions before the test.
For a cystoscopy, your doctor will clean the skin around your urethra (the tube coming out from the bladder) and use a topical gel to numb the area. They will insert the cystoscope into your urethra and up into your bladder. You may feel some pressure and an urge to urinate. Your doctor will drain your urine into a sterile container and then remove the catheter.
The procedure carries a small risk of infection or bleeding. Your doctor will send the urine sample to a laboratory for analysis and then will receive a report.
Clean catch urine sample
A clean catch urine sample is easy, noninvasive, and carries no risk. Otherwise known as a midstream urine sample, you can do a clean catch urine sample in a doctor’s office or in the comfort of your own home.
Your doctor’s office will provide a special container to collect the sample. Be sure to ask your doctor for specific instructions regarding the proper way to get the sample and where to bring it when you finish. Failure to follow instructions may provide a poor result, and you may have to repeat the test.
You will use special cleansing cloths to clean the skin around your urethra prior to the test. You will need to urinate a small amount into the toilet, and then stop the flow of urine. Then you will urinate into the sterile container until reaching the desired level. You may then finish urinating into the toilet.
In some cases, your doctor may want you to provide urine samples over the course of several days. Your doctor will send the urine sample to a laboratory for analysis and then will receive a report.
A pathologist will analyze the cells under a microscope to see if there are any abnormalities. They may also look at the cells in a culture dish to see if bacteria or other organisms are growing.
The pathologist will send the results of your urine cytology test to your doctor, who will report the results to you. Ask your doctor how long you can expect to wait for your results.
Your doctor will be able to explain what your results mean. There are some common terms that may describe your results:
- Negative. No cancer cells were identified.
- Atypical or suspicious. These terms describe when cells don’t appear normal, but it can’t be confirmed that they are cancerous or precancerous.
- Positive. Cancer cells have been found in the urine sample. Your report will likely say the test shows “the presence of cancer cells” rather than “positive.”
- Unsatisfactory. The sample could not be properly interpreted.
- Bostwick DG. (2020). Chapter 7: Urine Cytology. Urologic Surgical Pathology (Fourth Edition). https://www.sciencedirect.com/science/article/pii/B9780323549417000074
- O’Flynn H, et al. (2020). Diagnostic accuracy of cytology for the detection of endometrial cancer in urine and vaginal samples.
- The American Cancer Society medical and editorial content team. (2019). Can bladder cancer be found early?