Consecutive quantitative cytology in bladder cancer

Microsatellite Instability Analysis (MSA) for Bladder Cancer: Past History and Future Directions

Microsatellite instability (MSI), the spontaneous loss or gain of nucleotides from repetitive DNA tracts, is a diagnostic phenotype for gastrointestinal, endometrial, colorectal, and bladder cancers; yet a landscape of instability events across a wider variety of cancer types is beginning to be discovered. The epigenetic inactivation of the MLH1 gene is often associated with sporadic MSI cancers. Recent next-generation sequencing (NGS)-based analyses have comprehensively characterized MSI-positive (MSI+) cancers, and several approaches to the detection of the MSI phenotype of tumors using NGS have been developed. Bladder cancer (here we refer to transitional carcinoma of the bladder) is a major cause of morbidity and mortality in the Western world. Cystoscopy, a gold standard for the detection of bladder cancer, is invasive and sometimes carries unwanted complications, while its cost is relatively high. Urine cytology is of limited value due to its low sensitivity, particularly to low-grade tumors. Therefore, over the last two decades, several new "molecular assays" for the diagnosis of urothelial cancer have been developed. Here, we provide an update on the development of a microsatellite instability assay (MSA) and the development of MSA associated with bladder cancers, focusing on findings obtained from urine analysis from bladder cancer patients as compared with individuals without bladder cancer. In our review, based on over 18 publications with approximately 900 sample cohorts, we provide the sensitivity (87% to 90%) and specificity (94% to 98%) of MSA. We also provide a comparative analysis between MSA and other assays, as well as discussing the details of four different FDA-approved assays. We conclude that MSA is a potentially powerful test for bladder cancer detection and may improve the quality of life of bladder cancer patients.

Microsatellite analysis of voided-urine samples for surveillance of low-grade non-muscle-invasive urothelial carcinoma: feasibility and clinical utility in a prospective multicenter study (Cost-Effectiveness of Follow-Up of Urinary Bladder Cancer trial [CEFUB])

BACKGROUND

Microsatellite analysis (MA) of voided-urine samples has been promoted as an alternative for cystoscopy surveillance (UCS) of patients with low-grade non-muscle-invasive papillary urothelial carcinoma (UC).

OBJECTIVE

To assess the feasibility and clinical utility of MA on voided-urine samples in a routine setting to detect or predict bladder cancer recurrences.

DESIGN, SETTING, AND PARTICIPANTS

We evaluated 228 patients monitored by MA of voided-urine samples and synchronous UCS who participated in a longitudinal prospective study in 10 hospitals. Follow-up started after diagnosis of a primary or recurrent pTa, pT1, grade 1 or grade 2 papillary UC.

MEASUREMENTS

Clinico-pathological parameters and fibroblast growth factor receptor 3 (FGFR3) gene mutation status of the inclusion tumour were determined. MA outcome was analysed in 1012 urine samples during a mean follow-up of 41 mo. Poor DNA quality prevented MA in 19% (197/1012) of the samples, leaving 815 visits for a cross-sectional analysis of sensitivity and specificity. We determined the predictive value (PPV) in a longitudinal analysis for 458 series with persistent MA results. Factors influencing diagnostic quality of MA were investigated. Kaplan-Meier analysis was performed to relate MA results to recurrence.

RESULTS AND LIMITATIONS

Cross-sectional sensitivity and specificity of MA for detection of a recurrence were 58% (49/84) and 73% (531/731), respectively. One pT1 grade 3 UC was missed. In a longitudinal analysis, the 2-yr risk to develop a recurrence reached 83% if MA outcome was persistently positive and 22% when MA was persistently negative. PPV of MA was higher with wild-type FGFR3 gene status and smoking habits. All four upper urinary tract tumours detected were preceded by a positive MA test.

CONCLUSIONS

Consecutive positive MA results are a strong predictor for future recurrences, but sensitivity needs to be improved, for example, by patient selection and testing of additional genetic markers in urine samples.

Quantitative Cytology on Bladder Wash versus Voided Urine: A Comparison of Results

OBJECTIVES

Quantitative cytology (Quanticyt) is a valuable marker for the identification of high-risk superficial bladder cancer (SBC) patients and can be used to individualize surveillance of patients. A disadvantage is the necessity to perform an invasive procedure to obtain the required bladder wash sample. This study investigated whether quantitative cytology can be performed on voided urine with reliable results, consistent with the quantitative cytology performed on bladder wash samples.

METHODS

Between June 2003 and May 2005, 288 voided urine samples in combination with bladder wash samples were obtained from patients with SBC who visited our urologic outpatient department. Quantitative cytology was performed on all samples. Corresponding clinical pathologic features and washed cytopathology results were collected. Linear regression analyses were performed for comparison of results from both types of samples.

RESULTS

Ninety-one percent of the samples fell into the low or intermediate region on bladder wash. A clear deviation in the nuclear shape (MPASS) was seen in the voided urine samples, which led to more low-risk results. The clinical characteristics show that this shift is not the result of under-staging. The nuclear content (2c deviation index [DI]) did not change by performing the analysis on urine.

CONCLUSION

When urine is correctly processed after voiding, quantitative cytology can be done on these samples. Voided urine-based quantitative cytology can be implemented in daily practice.

Current bladder cancer tests: unnecessary or beneficial?

Bladder cancer is currently diagnosed using cystoscopy and cytology in patients with suspicious signs and symptoms. These same tests are used to monitor patients with a history of bladder cancer for recurrence. The recurrence rate for bladder cancer is high, thus necessitating long-term follow-up. Urine cytology requires an experienced cytopathologist and is costly. It has high specificity, but low sensitivity for low-grade bladder tumors. Recently many non-invasive bladder cancer tests, utilizing markers found in the urine, have been developed. The FDA has approved several of these for the use is bladder cancer diagnosis, and many others are undergoing development and investigation. An ideal bladder cancer test would be non-invasive, highly sensitive and specific, inexpensive, easy to perform, and yield highly reproducible results. Many of the tests reviewed meet some, but not all, of these criteria.

Bladder tumor markers for monitoring recurrence and screening comparison of hyaluronic acid-hyaluronidase and BTA-Stat tests

BACKGROUND

One of the goals of a noninvasive test for bladder carcinoma screening would be to reduce surveillance cystoscopies among patients with a history of bladder carcinoma. In addition, an accurate bladder carcinoma marker could be used to screen a high-risk population. The authors examined the efficacy of the hyaluronic acid-hyaluronidase (HA-HAase) and BTA-Stat tests to detect and predict bladder carcinoma recurrence and tested their specificity for bladder carcinoma screening.

METHODS

Over a four year period, the authors prospectively collected 225 urine specimens from 70 bladder carcinoma patients and analyzed them by the HA-HAase test. Tumors were identified during 178 visits, and in 47 specimens there was no evidence of disease (NED). Twenty six of these 70 patients were randomly selected to have the BTA-Stat test (111 surveillance visits). In a separate study, 401 former Department of Energy (DOE) workers, who are likely to be at a higher risk for bladder carcinoma, were screened by the HA-HAase and BTA-Stat urine tests.

RESULTS

The HA-HAase test had an approximately 91.0% sensitivity, 70% specificity, 87% accuracy, 92% positive predictive value (PPV), and 67% negative predictive value (NPV) in the 70 bladder carcinoma patients. There were 14 false-positives; however, 6 of these had recurred in approximately 5 months. Only 4 out of 33 NED cases recurred in that time period (chi-square = 5.43; degrees of freedom [DF] = 1; P = 0.0198). Thus, a false-positive HA-HAase test carried a significant risk of recurrence within five months (relative risk [RR] = 3.5; odds ratio [OR] = 5.44). In a direct comparison, the HA-HAase and BTA-Stat had 94% and 61% sensitivity, 63% and 74% specificity, 87% and 64% accuracy, 89% and 88% PPV, and 77% and 38% NPV, respectively. While 6 of the 10 false-positive on the HA-HAase test recurred in 5 months (chi-square = 9.6; DF = 1; P = 0.004), only 1 of the 7 false-positives on the BTA-Stat test recurred in that time period (chi-square = 0.096; DF = 1; P = 0.756). The RR and OR for the HA-HAase test were 10.2 and 24, and for the BTA-Stat, 1.4 and 1.5, respectively. In the DOE worker screening study, the HA-HAase and BTA-Stat had 14% (56 out of 401) and 16.7% (67 out of 401) positive rates, respectively. Sixty three percent of the positives on the BTA-Stat test, but only 25% of the positives on the HA-HAase test, had benign urologic conditions. None of the biomarker positive cases with clinical follow-up (n = 29) had evidence of bladder carcinoma.

CONCLUSIONS

The HA-HAase test is efficient and superior to the BTA-Stat for detecting and predicting bladder carcinoma recurrence. Noninvasive tests with low false positive rates could be used for bladder carcinoma screening in high-risk populations (e.g., those with occupational exposure to carcinogens or smokers).

Can biological markers replace cystoscopy? An update

Cystoscopy is currently considered the gold standard for the detection of bladder tumors. The role of urine cytology in the initial detection and follow-up of patients is under discussion. New elaborative and rapid assays are available that may circumvent the low sensitivity and poor reproducibility of urine cytology. The methods that have been tested extensively are the nuclear matrix protein (NMP22) assay, the BTA stat assay, and the BTA TRAK enzyme-linked immunosorbent assay. Both outperform cytology in the detection of low-grade lesions. The specificity of both assays, however, lags behind that of cytology. The data from retrospective analyses are insufficient to justify clinical integration, and the need to replace cystoscopy with these novel assays remains to be proven.