Urine cytology of urothelial cancerMedical editor Aasmund Berner MD
Oslo University Hospital
A constant rejection of cells from normal urothelium and malignant cells occurs in the bladder. These rejected cells can be isolated from a regular urine sample and assessed and classified as normal or malignant.
Urine cytology is most reliable for detecting tumors of higher grade (WHO grade 2 and 3) and Tis. A tumor of WHO malignancy grade 1 will give a positive cytology to a lesser degree. Due to a low cell count, degenerative -, irritative - (for example calculous disease or cystoscopy urine) and therapy-induced (BCG and radiation therapy) changes, the cytological interpretation of the specimen may be problematic.
- Hematuria not explained at cystoscopy and urography
- Ambiguous finding at cystoscopy
- Negative cystoscopy in patient with suspect UTI-symptoms
- Negative cystoscopy and possible tumor in upper urinary tract from urography/ultrasound
- Follow-up of certain patients (for exmple Tis)
- Reagent tube
- Slide glass with matted end
- 70% ethanol
- PreserveCyt solution
- ThinPrep machine
- Urine for a cytology examination is taken from spontaneous urine, catheter, or ilium bladder.
- Night urine should not be used.
- The sample is fixed with 70% ethanol/urine (50/50) and sent as a regular postal package
- At least two, preferably three samples should be taken for cytology, at different urinations.
- Pour the urine sample into a 50 ml reagent tube.
- Centrifuge the sample for 10 minutes at 2000 rotations.
- Remove the supernatant.
- Preserve the sediment with PreserveCyt solution and allow to sit for at least 15 minutes.
- Prepare the ThinPrep machine:
- Insert the filter with holder
- The "Fix-bath" holder should be filled with 70% ethanol.
- Have a ThinPrep slide ready.
- PreserveCyt solution container with the fixed material should be available.
- Start the machine (program 2)
- When the sample is finished rotating, remove the ThinPrep slide from the fix-bath holder.
- Allow the sample to dry.
- Stain by routine protocol in the staining machine with Papanicolaou. Remember: only one bath of hematoxylin.
- Mount the smears immediately. If not, place them in Xylenes to avoid "Cornflakes."