URINE CYTOLOGY AND URINARY MARKERS IN CA BLADDER

URINE CYTOLOGY AND URINARY MARKERS IN A CASE OF CA BLADDER

DR. SWAPNIL TOPLE

DNB UROLOGY

URINE CYTOLOGY

• Urine cytology, first introduced by Papanicolaou in 1945

• Evaluates the morphologic changes associated with bladder cancer

• It is the gold standard urinary marker against which other markers are held

• Sensitivity 40% to 62% • specificity 94% to 100%

• Positive urine cytology is virtually diagnostic of a bladder tumor, though the tumor is not endoscopically visible.

• The sensitivity and specificity of urine cytology is dependent on the:

Cytopathologistnumber of samples evaluated stage and grade of the tumorAssociated inflammation, infection, intra-

vesical instillations

• Instrumented urine during cystoscopy has improved sensitivity and specificity, but an invasive procedure is required

• 15% of patients with atypical cytology that is not diagnostic of cancer will have an underlying malignancy

• Thus patients with an atypical cytology need more frequent evaluation or repeat random bladder biopsies.

• Even in the setting of UC patients with a negative workup (cystoscopy and upper tract imaging) with a persistently positive cytology;

40% were found to have genitourinary cancer within 24 months, with a mean time to diagnosis of 5.6 months

• Although cytology has traditionally been believed to have high sensitivity for high-grade cancer and low sensitivity for low grade cancer, recent studies do not support this

• Thus cytology has high specificity but low sensitivity for both high-grade and low-grade tumors including CIS

Urine Markers for Urothelial Cancer

• BTA stat(qualitative) & BTA TRAK (quantitative)

• detect human complement factor H–related protein

• sensitivity 50% to 80%

specificity 50% and 75%

• These tests are more sensitive than cytology but can be falsely positive in patients with inflammation, infection, or hematuria

• ImmunoCyt:

• A hybrid of cytology and an immunofluorescent assay

• Three fluorescent labeled monoclonal antibodies are targeted at a UC variant of carcinoembryonic antigen and two bladder mucins.

• Sensitivity 86%

Specificity 79%

• not been shown to be affected by benign conditions, but interpretation is complex and operator dependent

• NMP-22 Bladder Chek Test

• Based on the detection of nuclear matrix protein 22, part of the mitotic apparatus released from urothelial nuclei upon cellular apoptosis.

• The protein is elevated in UC, but it is also released from dead and dying urothelial cells.

• Benign conditions of the urinary tract such as stones, infection, inflammation, hematuria, and cystoscopy can cause a false-positive reading.

• Both a laboratory-based, quantitative immunoassay and a qualitative point-of-care test are available.

• UroVysion (FISH):

• Fluorescence in-situ hybridization identifies fluorescently labeled DNA probes that bind to intranuclear chromosomes.

• The current commercially available probes evaluate aneuploidy for chr 3, 7, and 17 an homozygous loss of 9p 21

Sensitivity 79%

Specificity 70%

• UroVysion has the highest specificity of the available tumor markers

• Detects chromosomal changes before the development of phenotypic expression of malignancy, so it leads to an “anticipatory positive” reading in some patients

• Patients testing negative are unlikely to experience tumor recurrence in less than 1 year

• This may allow identification of patients at risk of recurrence versus those unlikely to recur in order to individualize surveillance protocols

• clarify equivocal findings in patients with atypical or negative cytology

• Not affected by hematuria, inflammation, or other factors that can cause false-positive readings with some tumor markers, so it appears to be useful as a marker of BCG response

• Microsatellite analysis

• Amplifies repeats in the genome that are highly polymorphic, and PCR amplification can detect tumor-associated loss of heterozygosity by comparing the peak ratio of the two alleles in tumor DNA in the urine sample with the presence of the alleles in a blood sample from the same individual

• Interestingly, if the microsatellite analysis:

persistently positive-83% 2-year recurrence rate

persistently negative-22% of patients had recurrent tumors

• standardization of the test will allow analysis without a blood sample, and this will significantly improve the patient’s acceptance

• The Lewis blood group antigen X

• Usually absent from urothelial cells in adults except for occasional umbrella cells

• There is increased Lewis X expression in bladder cancers

• It is independent of secretor status, grade, and stage.

• sensitivity 75%

specificity 85%

• There is no commercially available test to date

• CK 20 and CYFRA 21.1

• Fragments of cytoskeletal proteins that can be detected in the urine of bladder cancer patients by either protein or mRNA detection

• CK 20: sensitivity 85%

specificity 76%

• CYFRA 21.1: with a cutoff value of 4 ng/mL,

sensitivity 43%

specificity 68%

• CpG dinucleotide:

• Islands cluster around promoters in an unmethylated state to allow gene expression

• Methylation of the CpG islands shuts down the promoter, and if the promoter in question is part of a tumor suppressor gene then cancer can form.

• Survivin:

• An antiapoptotic protein that has a high expression in urothelial cancer

• Found in 10% to 30% of bladder cancers and is readily shed into the urine.

• Sensitivity 64% to 100%

specificity 87% to 93%

• This test may be useful in predicting which patients will respond to intravesical therapy

• Survivin was relatively poor at detecting advanced-stage or high-grade tumors

• Hylauronic acid:

• Controls intercellular communications and cell replication.

• Urothelial cancer induces hylauronic acid production from fibroblasts, and the amount correlates with the stage of the disease.

• sensitivity 91% to 100%

• specificity 84% to 90%

• TRAP:

• Telomerase resides at the terminal ends of the chromosomes and duplicates random DNA repeats to prevent cell death

• Telomerase activity is measured in telomeric repeat application protocol (TRAP) and is detected in 80% of urine from patients with bladder cancer with no grade differential.

• sensitivity 90%

specificity 88%

• Virtually all patients complain of pain and discomfort with an office cystoscopy

• Urine markers studies could forgo this pain in select situations as described above.

• However, patients reported that a urine marker study would need 90% sensitivity in order to replace office cystoscopy

• None of the currently available urinary markers meet this 90% sensitivity on a reliable basis

• Therefore a combination of cystoscopy with urine markers, in select situations, is appropriate for surveillance of patients with non–muscle-invasive bladder cancer

THANK YOU!!