Nuclear matrix protein-22: a prospective evaluation in a population at risk for bladder cancer. Results from the UroScreen study.

UNLABELLED: What's known on the subject? and What does the study add? The prognosis of bladder cancer significantly depends on tumour stage and time of diagnosis so early diagnosis is desirable to decrease mortality and treatment costs. The NMP22 test is approved for clinical application by the Food and Drug Administration (FDA) of the US. Previous studies have reported values of 47-100% for sensitivity and 58-91% for specificity with this test, but there is no new data on the predictive value of NMP22 for screening bladder cancer (BC). The most important risk factor for BC is the tobacco consumption but occupational exposure to carcinogenic substances, especially aromatic amines, is regarded as another risk factor. The UroScreen study is a prospective longitudinal study for the early detection of BC. To our knowledge, it is the largest prospective validation study conducted over the longest period of time. The study results led us to conclude that, based on the currently available data, NMP22 should not be regarded as an alternative to endoscopy, and we could not make a general recommendation for screening or follow-up. The UroScreen results indicate that urine-based molecular markers could be a suitable addition to urine cytology and the detection of microhaematuria. OBJECTIVE: To evaluate the value of nuclear matrix protein-22 (NMP22) in bladder cancer (BC) screening, and its effect on variables in a prospective study in a high-risk population. PATIENTS AND METHODS: A total of 1772 chemical workers (mean age 62 years) exposed to carcinogenic aromatic amines were enrolled in the study. In all, 7091 screening check-ups in 1609 subjects were performed. Urine samples were collected for a quantitative NMP22 immunoassay, urine analysis and creatinine concentration assessment. Cystoscopy and subsequent transurethral resection were performed where there were suspicious findings. RESULTS: Histopathological analysis found three papillary urothelial neoplasms of low malignant potential, five recurrent BCs and 13 primary BCs. Three tumours were at a muscle-invasive stage (pT2, pT3a or pT3b). We found higher NMP22 concentrations (>10 U/mL) in 224 patients, which correctly predicted BC in six cases (sensitivity 97.29%, specificity 28.57%; negative predictive value 99.04%, positive predictive value 12.24%). Gross haematuria affected NMP22 results (odd ratio [OR] 3.49, 95% confidence interval [CI] 1.81-6.73). Infection also affected NMP22 results (OR 4.13, 95% CI 2.31-7.35). NMP22 was more frequently positive in urine with creatinine concentration >2.5 g/L (OR 1.61, 95% CI 0.91-2.86). CONCLUSIONS: NMP22 outcomes are affected by haematuria, infection and concentrated urine. NMP22 alone cannot be recommended for primary screening in a high-risk population nor as an alternative to cystoscopy during follow-up. A NMP22 test might be a useful adjunct to urine cytology.

The role of haematuria in bladder cancer screening among men with former occupational exposure to aromatic amines.

UNLABELLED: Study Type - Diagnostic (validating cohort). LEVEL OF EVIDENCE: 1b. What's known on the subject? and What does the study add? Microscopic haematuria (µH) is frequently detected in elderly adults. The American Urological Association recommends the follow-up of subjects with µH on bladder cancer. Whereas gross haematuria is considered an important sign of the presence of bladder cancer, the disease-predictive value of µH is less clear. No association of µH with the development of bladder tumours in a prospective screening cohort of chemical workers was observed. The positive predictive value of µH for bladder cancer was as low as 1.2%. Haematuria interfered with NMP22 but not with cytology and UroVysion(TM) test results. OBJECTIVE: • To assess the positive predictive value (PPV) of microhaematuria (µH) and gross haematuria (GH) in bladder cancer screening and the influence of haematuria on tumour tests in a prospective study. PATIENTS AND METHODS: • From September 2003 to January 2010, 1323 men took part in an annual voluntary bladder cancer screening programme for chemical workers with former exposure to aromatic amines. • In 5315 urine samples haematuria was determined with a dipstick, followed by a microscopic blood cell count in the sediment. Haematuria was categorized into traces, µH and GH. • Urinary leukocytes and other factors were investigated as potential predictors of haematuria using a generalized estimating equation model for repeated urinalysis. The risk of haematuria for positive tumour tests was analysed correspondingly. • The bladder cancer risk was estimated for the highest degree of haematuria occurring during the study with Poisson regression. RESULTS: • As of July 2010, 15 bladder tumours were detected in 14 participants. • GH was found in four out of nine high-grade tumours and associated with a rate ratio of 3.82, 95% confidence interval (CI) 0.50-29.15 for the development of bladder lesions. • The PPV of GH was 11.4%, but only 1.2% for µH. µH occurred in 18.8% of urine samples and was not associated with bladder cancer [rate ratio (RR) 0.72, 95% CI 0.11-4.78]. • Abundant urinary leukocytes were associated with µH [odds ratio (OR) 8.34, 95% CI 2.26-30.69] and even stronger with GH (OR 22.25, 95% CI 6.42-77.06). • Haematuria and leukocytes influenced NMP22 positivity (µH: OR 1.63, 95% CI 1.06-2.51, abundant leukocytes: OR 8.90, 95% CI 1.58-50.16), but not test results for urine cytology and UroVysion(TM) . CONCLUSION: • While the PPV of µH for bladder cancer was low, there was a strong influence of haematuria and leukocytes on the protein-based tumour test NMP22®. • Erythrocytes and leukocytes should be determined at least semi-quantitatively for the interpretation of positive NMP22 test results. • In addition, a panel of tumour tests that includes methods not affected by the presence of erythrocytes or leukocytes such as cytology and UroVysion(TM) would improve bladder cancer screening.

Performance of survivin mRNA as a biomarker for bladder cancer in the prospective study UroScreen.

BACKGROUND: Urinary biomarkers have the potential to improve the early detection of bladder cancer. Most of the various known markers, however, have only been evaluated in studies with cross-sectional design. For proper validation a longitudinal design would be preferable. We used the prospective study UroScreen to evaluate survivin, a potential biomarker that has multiple functions in carcinogenesis. METHODS/RESULTS: Survivin was analyzed in 5,716 urine samples from 1,540 chemical workers previously exposed to aromatic amines. The workers participated in a surveillance program with yearly examinations between 2003 and 2010. RNA was extracted from urinary cells and survivin was determined by Real-Time PCR. During the study, 19 bladder tumors were detected. Multivariate generalized estimation equation (GEE) models showed that ß-actin, representing RNA yield and quality, had the strongest influence on survivin positivity. Inflammation, hematuria and smoking did not confound the results. Survivin had a sensitivity of 21.1% for all and 36.4% for high-grade tumors. Specificity was 97.5%, the positive predictive value (PPV) 9.5%, and the negative predictive value (NPV) 99.0%. CONCLUSIONS: In this prospective and so far largest study on survivin, the marker showed a good NPV and specificity but a low PPV and sensitivity. This was partly due to the low number of cases, which limits the validity of the results. Compliance, urine quality, problems with the assay, and mRNA stability influenced the performance of survivin. However, most issues could be addressed with a more reliable assay in the future. One important finding is that survivin was not influenced by confounders like inflammation and exhibited a relatively low number of false-positives. Therefore, despite the low sensitivity, survivin may still be considered as a component of a multimarker panel.