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# Urine Cytology
The gold standard of diagnosing bladder cancer is urine cytology and transurethral (through the urethra) cystoscopy.
How the test is performed:
Collect a urine specimen and send it to the laboratory.
Collect a "clean-catch" (midstream) urine sample. To obtain a clean-catch sample, men or boys should wipe clean the head of the penis. Women or girls need to wash the area between the lips of the vagina with soapy water and rinse well. As you start to urinate, allow a small amount to fall into the toilet bowl (this clears the urethra of contaminants). Then, in a clean container, catch about 1-2 ounces of urine and remove the container from the urine stream. Give the container to the health care provider or assistant.
How to prepare for the test:
Collect a clean catch urine sample 3 hours after the last voiding. The first morning voided specimen should not be used.
A test for cancer cells in the urine. This is called a cytology test or voided urinary cytology test (VUC). It involves a specialist examining a sample of urine under the microscope to look for cancer cells. It may take up to 2 weeks to get the results.
Cytology tests can be helpful to doctors in diagnosing some types of bladder cancer, such as cancer in situ (CIS), that are more difficult to detect with a cystoscopy. However, not all samples of urine contain cancer cells, even when there is cancer in the bladder. This means the test may give a negative result even if there is a cancer. This is called a false negative result. A false negative result is more likely for early bladder cancers and for bladder cancers that are slow growing (low grade). So, if a cytology test is negative ,for cancer further tests may still need to be done.
Why the test is performed
The test is done to detect cancer and inflammatory diseases of the urinary tract. The test is often done when bladder lesions are noted on an x-ray.
The test may occasionally be ordered for individuals who are at high risk of developing bladder cancer. The test can also detect cytomegalovirus and other viral diseases.
Normal Values
The urine shows normal cells and is relatively free of debris.Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results meanAbnormal cells in the urine may be a sign of inflammation of the urinary tract orcancer of the kidney, ureters, bladder, or urethra.
From: clinicalanswers.nhs.uk
" A 2003 article reviewed as part of the NHD Centre for Reviews and Dissemination DARE programme [1]. It reported:
“Cytology had a pooled specificity of 94% (95% confidence interval, CI: 90, 96), which was statistically significantly higher than for other tests”
And reported the sensitivity of cytology as 55% (95% CI: 48, 62). The author of the original article concludes:
“Cytology had the best specificity and telomerase the best sensitivity. None of the tests reached a level of sensitivity that would be acceptable to clinical practice.”
An American guideline “Screening for bladder cancer in adults: recommendation statement” [2] has a Q&A section and one of the questions was "What are the accuracy and reliability of feasible screening tests for bladder cancer?" which answers:
“Several studies examined the accuracy of hematuria, bladder tumor antigen, NMP22 urinary enzyme immunoassay, and urine cytology. All had important flaws, especially involving screening patients from urology clinics (as opposed to average risk populations from primary care clinics) or not applying "gold standard" tests (cystoscopy with or without biopsy) to those who screened negative for bladder cancer. As a result, these studies do not provide high-quality evidence about the accuracy of screening tests in the general primary care population.” "
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