Impact of implementing the first edition of the Paris system for reporting: A systematic review and meta-analysis

Urine cytology is a noninvasive, widely used diagnostic tool for screening and surveillance of genitourinary tract neoplasms. However, the absence of unified terminology and clear objective morphological criteria limits the clinical benefit of urine cytology. The Paris System for Reporting Urine Cytology (TPS) was developed with the goal of standardizing reporting and improving urine cytology performance in detecting high-grade malignancy (HGM). We aimed to evaluate potential effects of TPS on improving urine cytology diagnostic performance and clinical utility by conducting a systematic review and meta-analysis. We searched six electronic databases to identify cross-sectional and cohort studies written in English assessing the accuracy of urine cytology in detecting genitourinary tract malignancies of patients under surveillance or with clinical suspicion of malignancy from January 2004 to December 2022. We extracted relevant data from eligible studies to calculate relative distribution of cytology diagnostic categories; ratio of atypical to HGM cytology diagnosis; and risk of HGM (ROHGM) and HGM likelihood ratio (HGM-LR) associated with cytology diagnostic categories. We used a generalized linear mixed model with logit transformation to combine proportions and multilevel mixed-effect logistic regression to pool diagnostic accuracy measurements. We performed meta-regression to evaluate any significant difference between TPS and non-TPS cohorts. We included 64 studies for 99,796 combined total cytology samples, across 31 TPS and 49 non-TPS cohorts. Pooled relative distribution [95% confidence interval (CI)] of negative for high-grade urothelial carcinoma (NHGUC)/negative for malignancy (NM); atypical urothelial cells (AUC); suspicious for high-grade urothelial carcinoma (SHGUC)/suspicious for malignancy (SM); low-grade urothelial neoplasm (LGUN); and HGM categories among satisfactory cytology cases were 83.8% (80.3%-86.9%), 8.0% (6.0%-10.6%), 2.2% (1.4%-3.3%), 0.01% (0.0%-0.1%), and 4.2% (3.2%-5.5%) in TPS versus 80.8% (76.8-2.7%), 11.3% (8.6%-14.7%), 1.8% (1.2%-2.7%), 0.01% (0.0%-0.1%), and 3.3% (2.5%-4.3%) in non-TPS cohorts. Adopting TPS classification resulted in a significant increase in the frequency of NHGUC and a reduction in AUC cytology diagnoses, respectively. The AUC/HGM ratio in TPS cohort was 2.0, which showed a statistically significant difference from the atypical/HGM ratio of 4.1 in non-TPS cohort (p-value: 0.01). Moreover, the summary rate (95% CI) of LGUN called AUC on cytology significantly decreased to 20.8% (14.9%-28.3%) in the TPS compared with 34.1% (26.4%-42.8%) in non-TPS cohorts. The pooled ROHGM (95% CI) was 20.4% (6.2%-50.0%) in nondiagnostic (NDX), 15.5% (9.6%-24.2%) in NHGUC, 40.2% (30.9%-50.2%) in AUC, 80.8% (72.9%-86.8%) in SHGUC, 15.1% (5.7%-34.3%) in LGUN, and 91.4% (87.3%-94.3%) in HGM categories in TPS studies. NHGUC, AUC, SHGUC, and HGM categories were associated with HGM-LR (95% CI) of 0.2 (0.1-0.3), 0.9 (0.6-1.3), 6.9 (2.4-19.9), and 16.8 (8.3-33.8). Our results suggest that TPS 1.0 has reduced the relative frequency of AUC diagnosis, AUC/HGM ratio, and the frequency of LGUNs diagnosed as AUC on cytology. Adopting this classification has improved the clinical utility of SHGUC and HGM cytology diagnoses in ruling in high-grade lesions. However, an NHGUC diagnosis does not reliably rule out the presence of a high-grade lesion.

Preoperative fluorescence in situ hybridization analysis as a predictor of tumor recurrence in patients with non-muscle invasive bladder cancer: a bi-institutional study

BACKGROUND

Non-muscle invasive bladder cancer (NMIBC) is known for its elevated recurrence rate, necessitating an enhancement in the current risk stratification for recurrence. The urine-based fluorescence in situ hybridization (FISH) assay has emerged as a noninvasive auxiliary tool for detecting bladder cancer. The aim of this study was to explore the potential relationship between the preoperative FISH assay and recurrence, and to develop a FISH-clinical nomogram for predicting the recurrence-free survival (RFS) in NMIBC patients.

METHODS

In total, 332 eligible patients were enrolled from two hospitals. The SYSMH cohort was randomly assigned to the training set (n = 168) and the validation set I (n = 72) at a ratio of 7:3, while the SYSUTH cohort was allocated to the validation set II (n = 92). The correlation between the preoperative FISH assay and recurrence was determined through the Cox regression analysis. The least absolute shrinkage and selection operator (LASSO) Cox regression algorithm was used for model construction. The performance of the model was assessed by its discrimination, calibration, and clinical usefulness.

RESULTS

We uncovered that chromosome 7 aneuploidy, p16 locus loss, number of the positive FISH sites, and the FISH test result were significantly associated with tumor recurrence. Then, a FISH-clinical nomogram incorporating the FISH test result, T stage, associated CIS, tumor grade, and tumor status was developed. It showed favorable calibration and discrimination with a C-index of 0.683 (95%CI, 0.611-0.756) in the training set, which was confirmed in the validation set I and validation set II with C-indexes of 0.665 (95%CI, 0.565-0.765) and 0.778 (95%CI, 0.665-0.891), respectively. Decision curve analysis revealed the clinical usefulness of the nomogram. Moreover, our proposed nomogram significantly outperformed the guideline-recommended EORTC and CUETO scoring models.

CONCLUSION

Our study confirmed the prognostic value of the preoperative FISH assay and proposed a FISH-clinical nomogram to predict RFS in NMIBC patients. Our nomogram can serve as a more precise tool for recurrence risk stratification, which may optimize disease management in bladder cancer and improve patient prognosis.

High-grade urothelial carcinoma with hypochromatic chromatin in urine cytology

INTRODUCTION

Some high-grade urothelial carcinomas (UCs) in urine cytology have hypochromatic chromatin, but the incidence and criteria for diagnosis are not well described.

MATERIALS AND METHODS

Urine cytology cases with biopsy follow up were reviewed.

RESULTS

Cytospin preparations from 331 cases with biopsy follow up (230 benign/low-grade UC, 101 malignant) were reviewed. There were no false-positive cases. Cases with malignant cells with hypochromatic chromatin were identified in a total of 17 cases (16.8% of all malignancies). These comprised 2 carcinoma in situ, 11 high-grade papillary UC, 3 invasive UC, and 1 adenocarcinoma. Sixteen of 93 high-grade UCs (17.2%) had cells with hypochromatic chromatin. These cells were the only type of malignant cell in 4 of 101 cases (4.0%). All cases had cells with high nuclear-to-cytoplasmic ratios and markedly indented and irregular nuclear membranes that could be identified on both cytology and subsequent histology.

CONCLUSIONS

Malignant urothelial cells in urine cytology with hypochromatic chromatin can be present in 17% of cases and can be diagnosed as "positive for malignancy" based on their high nuclear-to-cytoplasmic ratio, and markedly indented and irregular nuclear membranes.

Association of chromosome 7 aneuploidy measured by fluorescence in situ hybridization assay with muscular invasion in bladder cancer

Background

The preoperative prediction of muscular invasion status is important for adequately treating bladder cancer (BC) but nevertheless, there are some existing dilemmas in the current preoperative diagnostic accuracy of BC with muscular invasion. Here, we investigated the potential association between the fluorescence in situ hybridization (FISH) assay and muscular invasion among patients with BC. A cytogenetic‐clinical nomogram for the individualized preoperative differentiation of muscle‐invasive BC (MIBC) from non‐muscle‐invasive BC (NMIBC) is also proposed.

Methods

All eligible BC patients were preoperatively tested using a FISH assay, which included 4 sites (chromosome‐specific centromeric probe [CSP] 3, 7, and 17, and gene locus‐specific probe [GLP]‐p16 locus). The correlation between the FISH assay and BC muscular invasion was evaluated using the Chi‐square tests. In the training set, univariate and multivariate logistic regression analyses were used to develop a cytogenetic‐clinical nomogram for preoperative muscular invasion prediction. Then, we assessed the performance of the nomogram in the training set with respect to its discriminatory accuracy and calibration for predicting muscular invasion, and clinical usefulness, which were then validated in the validation set. Moreover, model comparison was set to evaluate the discrimination and clinical usefulness between the nomogram and the individual variables incorporated in the nomogram.

Results

Muscular invasion was more prevalent in BC patients with positive CSP3, CSP7 and CSP17 status (OR [95% CI], 2.724 [1.555 to 4.774], P < 0.001; 3.406 [1.912 to 6.068], P < 0.001 and 2.483 [1.436 to 4.292], P = 0.001, respectively). Radiology‐determined tumor size, radiology‐determined clinical tumor stage and CSP7 status were identified as independent risk factors of BC muscular invasion by the multivariate regression analysis in the training set. Then, a cytogenetic‐clinical nomogram incorporating these three independent risk factors was constructed and was observed to have satisfactory discrimination in the training (AUC 0.784; 95% CI: 0.715 to 0.853) and validation (AUC 0.743; 95% CI: 0.635 to 0.850) set. The decision curve analysis (DCA) indicated the clinical usefulness of our nomogram. In models comparison, using the receiver operator characteristic (ROC) analyses, the nomogram showed higher discriminatory accuracy than any variables incorporated in the nomogram alone and the DCAs also identified the nomogram as possessing the highest net benefits at wide range of threshold probabilities.

Conclusion

CSP7 status was identified as an independent factor for predicting muscular invasion in BC patients and was successfully incorporated in a clinical nomogram combining the results of the FISH assay with clinical risk factors.

The Paris System for reporting urinary cytology in daily practice with emphasis on ancillary testing by multiprobe FISH

Aims

The Paris System (TPS) was introduced in the diagnostic routine with the goal to simplify and standardise diagnostic reporting of urinary cytology. The diagnostic categories of TPS are based on defined cytological criteria, with a focus on high-grade urothelial carcinoma (HGUC). While the categories ‘negative for HGUC (NHGUC)’ and ‘HGUC’ are straightforward, the categories ‘atypical urothelial cells (AUC)’ and ‘suspicious of HGUC (SHGUC)’ remain inconclusive. In this study, we evaluated the feasibility of TPS in daily practice with special emphasis on ancillary fluorescence in situ hybridisation (FISH) testing in the setting of TPS categories.

Methods

In a 19-month period, TPS was prospectively applied in the routine diagnostic setting on 3900 urinary cytology cases comprising bladder and upper urinary tract washings and voided urine specimens. Additionally, we analysed the results of the FISH assay UroVysion prospectively performed on a cohort of 128 cases enriched for AUC and SHGUC categories.

Results

The most frequently reported category was NHGUC (n=3496, 89.7%), followed by AUC (n=178, 4.6%), HGUC (n=155, 4%), SHGUC (n=61, 1.6%), low-grade urothelial neoplasia (n=6, 0.1%) and other malignancies (n=4, 0.1%). In the FISH cohort, 40/90 (44%) cases within the AUC category were FISH positive, consistent with urothelial neoplasia. In the SHGUC category, 16/21 (76%) cases were FISH positive.

Conclusions

When prospectively applying TPS in urinary cytology, inconclusive atypia accounts only for a small subset of cases. FISH additionally improves the stratification between reactive and malignant cells in the indeterminate AUC and SHGUC categories.

Diagnostic Utility of UroVysion Combined With Conventional Urinary Cytology for Urothelial Carcinoma of the Upper Urinary Tract

OBJECTIVES

We prospectively evaluated the utility of UroVysion in urothelial carcinomas of the upper urinary tract (UCUUTs).

METHODS

Ninety patients who received nephroureterectomy for UCUUT were enrolled. We performed urinary cytology and UroVysion before nephroureterectomy. We also performed the assays on 23 volunteers without a history of urothelial carcinoma.

RESULTS

Seventy-five high-grade urothelial carcinomas (HGUCs), 10 low-grade urothelial carcinomas, and five other conditions were enrolled. Sensitivity, specificity, positive predictive value, and negative predictive value for HGUC detection by urinary cytology were 28.0%, 100.0%, 100.0%, and 31.6%, respectively; for detection by fluorescence in situ hybridization, these values were 60.0%, 84.0%, 93.8%, and 41.2%, respectively. UroVysion detected the only deletion of 9p21 in eight of 23 samples negative for HGUC by urinary cytology and in three of 23 volunteers.

CONCLUSIONS

Combining urinary cytology and UroVysion can improve the diagnostic accuracy of UCUUT. Caution is advised in diagnosing UCUUT based only on deletion of 9p21.

The Paris System for Reporting Urinary Cytology: early review of the literature reveals successes and rare shortcomings

The Paris System for Reporting Urinary Cytology (TPS) provides recommendations for the diagnosis of urinary tract cytology (UTC) specimens and has found acceptance on an international level. Since the official release of TPS in 2016, numerous research studies have been published analyzing its impact. This review summarizes the studies published since the release of TPS, highlighting areas in which TPS has performed well and other areas in which TPS may need improvement.

Performance of the UroVysion® FISH assay for the diagnosis of malignant effusions using two cutoff strategies

The cytological examination of cavity fluids has limited sensitivity in the diagnosis of malignancy. Aneuploidy, which is commonly observed in neoplastic cells, could potentially be used as an ancillary diagnostic tool. To evaluate the detection of aneuploid cells in cavitary effusion samples using the fluorescence in situ hybridization (FISH) assay UroVysion^® with some adaptations and two different cutoff strategies. Seventy samples of pleural or peritoneal fluid with positive (n = 40), negative (n = 15), or suspicious (n = 15) oncotic cytology were subjected to FISH assay with the multitarget UroVysion^® kit, which is composed of probes that hybridize to the centromeric region of chromosomes 3, 7, and 17 and to the locus 9p21. FISH performance was evaluated using two different cutoffs: (1) the manufacturer's cutoff (M‐FISH) and 2) a proposed cutoff (P‐FISH). Using M‐FISH, the diagnostic sensitivity was 57.1%, specificity 87.5%, and accuracy 60.0%; with P‐FISH, the sensitivity was 87.3%, specificity 71.4%, and accuracy 85.7%. When combined with cytology, the sensitivity, specificity, and accuracy were 88.0%, 83.3%, and 87.8%, respectively. Malignant cells presented a predominance of chromosomal gains. The UroVysion^® test using the P‐FISH cutoff was effective in demonstrating aneuploid cells in all malignant effusions, confirming the diagnosis of malignancy even in cases with suspicious cytology.

Detection of Bladder Cancer in Urine Sediments by a Novel Multicolor Fluorescence In Situ Hybridization (Quartet) Test

BACKGROUND

Bladder cancer is among the common human malignancies that show a heavy mutational load and copy number variations of numerous chromosomes, which makes them a target for diagnostic explorations.

OBJECTIVE

We aimed to design a multicolor fluorescence in situ hybridization (FISH) test referred to as the quartet test for the detection of bladder cancer in urine.

DESIGN, SETTING, AND PARTICIPANTS

We performed genome-wide copy number variation analysis on cohorts from the University of Texas MD Anderson Cancer Center (n=40) and The Cancer Genome Atlas (n=129), and identified the most frequently amplified chromosomal regions. These data were used to select four of the amplified regions to design a multicolor FISH test, referred to as the quartet test. Assay validation was performed on urine samples from 98 patients with bladder cancer: 56 with low-grade papillary, 42 with high-grade invasive disease, and 48 benign controls.

INTERVENTION

The quartet test can be used in clinical practice for noninvasive detection of bladder cancer.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We initially analyzed samples using a fraction of abnormal cell scores and then by the quantitative score, which included not only the proportion of cells with abnormal copy numbers, but also the proportion of cells with numbers of altered copies and degree of amplification. We used receiver operator characteristic (ROC) curves to identify cutoff values for the scores at which performances of sensitivity and specificity were maximized.

RESULTS AND LIMITATIONS

The copy number status assessed by probes detected in voided urine reflected the amplification status of the primary tumor. An ROC curve summarizing the proportion of assayed cells with any abnormal copy numbers gave specificity of 93.8% and sensitivity of 78.6% using the proportion of cells with abnormal copy numbers. The quantitative score giving extra weight to cells with multiple simultaneous amplifications provided 95.8% specificity and 76.8% sensitivity. Both percentage of abnormal cells and quantitative scores were highly effective for assessing the grade of the tumor. The full spectrum of potential clinical applications was not explored in the current study, and further validation studies are needed.

CONCLUSIONS

The quartet test shows promising specificity and sensitivity results, but it requires validation on a larger multi-institutional cohort of samples.

PATIENT SUMMARY

The quartet test can be used for noninvasive detection of bladder cancer in voided urine. It can also be used to assess the grade of the tumor and tumor recurrence as well as post-treatment effects.

High-grade urothelial carcinoma in urine cytology with jet black and smooth or glassy chromatin

BACKGROUND

Some high-grade urothelial carcinomas (UCs) in urine cytology can have jet black, smooth, or glassy chromatin, but to the authors' knowledge, the incidence and criteria for diagnosis are not well described. The current study was performed to define the incidence and appearance of high-grade UC in urine cytology in cytospin preparations with jet black and smooth or glassy chromatin.

METHODS

Cytospin preparations from 331 cases with biopsy follow-up (230 benign/low-grade UCs and 101 malignant UCs) were reviewed.

RESULTS

Cases with malignant cells with jet black and smooth or glassy chromatin were identified in a total of 60 cases (59.4% of all malignancies). These comprised 18 carcinoma in situ cases, 28 high-grade papillary UCs, 8 invasive UCs, 3 squamous cell carcinomas, 2 adenocarcinomas, and 1 melanoma. Of the 93 high-grade UCs, 51 (54.8%) had cells with either jet black and smooth or glassy chromatin. These cells were the only type of malignant cell in 6 of 101 cases (5.9%). All cases had at least 50 cells with jet black nuclei. Nuclei with jet black and smooth chromatin often were smaller than normal urothelial cells, often but not always elongate, had irregular nuclear outlines including pointed areas, and usually were accompanied by necrosis. Cells with glassy chromatin often were larger than normal urothelial cells, had rounder but still irregular nuclei, and also had frequent necrosis.

CONCLUSIONS

Malignant urothelial cells in urine cytology with jet black chromatin are common and can be diagnosed as "positive for malignancy" based on their irregular nuclear outline, increased cellularity (≥50 abnormal cells), and frequent necrosis. Cancer Cytopathol 2018;126:64-8. © 2017 American Cancer Society.

Utility of Fluorescence In Situ Hybridization (FISH) to Sub-Classify Low-Grade Urothelial Carcinoma for Prognostication

Background

Fluorescence in situ hybridization (FISH) is used widely to detect cancer levels, but its value in urothelial carcinoma remains unclear. The aim of this study was to use FISH to examine the urine specimens of low-grade urothelial carcinoma (UC) patients to determine the possibility of sub-classifying the prognosis of UC.

Material/Methods

We diagnosed 107 patients with low-grade UC using a UroVysion kit to detect chromosomes 3, 7, 17, and P16 in the urine. An average 46.6-month follow-up completed in January 2016 combined with the clinical follow-up data were evaluated with Spearman’s correlation analysis to analyze the aberration of chromosomes in relation to the prognostication. Univariate and multivariate analysis using the Mantel-Cox log-rank test for overall, cancer-specific, and disease-free survival were used to determine the prognostic significance of CSP7/CSP17 and CSP3/GLPp16.

Results

In the 107 samples, 84 showed positive reaction in the FISH test. Furthermore, CSP7/CSP17 was found to be significantly related with age, tumor size, T stage, and tumor numbers, but not in CSP3/GLPp16. In addition, Kaplan-Meier analysis and Cox proportional hazards regression revealed a significant negative correlation between CSP7/CSP17 and survival, while CSP3/GLPp16 showed no significantly differences.

Conclusions

CSP7/CSP17 positivity on FISH test appears to play a critical role in low-grade UC and may be considered as a high-risk and prognosis factor.

[Preneoplastic lesions and precursors of urothelial cancer]

As even a mere thickening of the urothelium can harbor genetic changes identical to that of low grade papillary urothelial tumors, it is not always possible to clearly recognize a precursor lesion of urothelial carcinoma by routine histological diagnostics. Complementary immunohistochemical and molecular diagnostic methods assist the recognition of these entities. These methods especially help to identify clinically important genetically unstable cells as the hallmark of carcinoma in situ (CIS). Little is known about the clinical significance of the morphological subtypes of CIS, which range from large cell to micropapillary variants. For a better understanding of special types of bladder cancer (e.g. adenocarcinoma and squamous cell carcinoma), it seems to be important to define the phenotype and the molecular pattern of non-urothelial lesions, such as intestinal metaplasia and squamous metaplasia, better and more precisely.