Screening and monitoring for bladder cancer: refining the use of NMP22.

Abstract

PURPOSE:

While detecting bladder cancer, bladder tumor markers demonstrate improved sensitivity compared with urinary cytology but the current limitation is the low specificity and positive predictive value, that is high false-positive rate. We examined the clinical categories of the false-positive results, established relative exclusion criteria, and recalculated the specificity and positive predictive value of this assay with these criteria.

MATERIALS AND METHODS:

A total of 608 patients considered at risk for bladder cancer presented to a urology clinic and submitted a single urine sample. Of the 608 patients 529 (87%) presented with de novo hematuria or chronic voiding symptoms without a diagnosis of bladder cancer. There were 79 (13.0%) patients being monitored with a known history of bladder cancer. Each urine sample was examined via cytology, urinalysis, culture and NMP22 protein assay. All patients underwent office cystoscopy, and transurethral resection and/or biopsy if a bladder tumor was suspected.

RESULTS:

Of the 608 patients 226 (37.2%) presented with microscopic hematuria, 143 (23.5%) with gross hematuria and 239 (39.3%) had chronic symptoms of urinary frequency or dysuria. There were 52 (8.6%) patients who had histologically confirmed bladder cancer. Of these 52 cancers NMP22 detected 46 (88.5%), whereas cytology identified only 16 (30.8%). When atypical cytology was considered positive, cytology detected 32 (61.5%) cases. In the 135 patients with increased NMP22 values the 46 identified tumors were accompanied by 89 false-positive values yielding a specificity of 83.9% and a positive predictive value of 34.1%. These false-positive results were divided into 6 clinical categories. Exclusion of these categories improved the specificity and positive predictive value of NMP22 to 99.2% and 92.0%, respectively, yielding results similar to urinary cytology (99.8% and 94.1%).

CONCLUSIONS:

Awareness and exclusion of the categories of false-positive results can increase the specificity and positive predictive value of NMP22, enhancing the clinical use of this urinary tumor marker.

• Authors: L E Ponsky, S Sharma, L Pandrangi, S Kedia, D Nelson, A Agarwal, C D Zippe
• Journal: The Journal of urology (J Urol) Vol. 166 Issue 1 Pg. 75-8 (Jul 2001) ISSN: 0022-5347 [Print] United States
• PMID: 11435827 (Publication Type: Clinical Trial, Comparative Study, Journal Article)

Chemical References

• Biomarkers, Tumor
• Nuclear Proteins
• nuclear matrix protein 22

Topics

• Aged
• Aged, 80 and over
• Biomarkers, Tumor (analysis)
• Biopsy, Needle
• Female
• Humans
• Male
• Mass Screening (methods)
• Middle Aged
• Monitoring, Physiologic (methods)
• Nuclear Proteins (analysis, urine)
• Predictive Value of Tests
• Probability
• Sensitivity and Specificity
• Urinary Bladder Neoplasms (diagnosis, urine)