Urinary Tract Cytopathology: Current and Future Impact on Patient Care.

Urine cytology is a non-invasive, cost-efficient, and sensitive test to detect high-grade urothelial carcinoma. The Paris System (TPS) for Reporting Urinary Cytology is an evidence-based system that uses the risk of malignancy to guide patient management. Since its inception, TPS has standardized urine cytology reports, facilitating communication among pathologists and between pathologists and clinicians. It is imperative to correlate the urine cytology findings with the concurrent tissue sample to avoid false-negative and false-positive results when possible. Several ancillary tests and artificial intelligence algorithms are being developed to increase the accuracy of urine cytology interpretation.

[A real-world study of the clinical application of the Paris system for reporting urinary cytology in cancer hospital].

Objectives: To evaluate the clinical value of the Paris system for reporting urinary cytology (TPS) in the diagnosis of urothelial carcinoma (UC). Methods: A total of 1 744 cytological diagnostic records (from 751 cases) were collected retrospectively. All specimens were voided urines and histopathology as the gold standard. The sensitivity and specificity of urinary cytological diagnosis of UC and risk of high grade malignant (ROHM) in each diagnostic category were compared. Results: There were 360 cases with histopathology. The percentage of negative for high-grade urothelial carcinoma (NHGUC) was 30.1% (226/751), atypical urothelial cells (AUC) was 29.8% (224/751), suspicious for high-grade urothelial carcinoma (SHGUC) was 16.8% (126/751), high grade urothelial carcinoma (HGUC) was 21.2% (159/751), and non-urothelial malignancy (NUM) was 2.1% (16/751). The histpathologic ROHM corresponding to each cytological diagnosis category were 27.3% for NHGUC, 32.7% for AUC, 74.7% for SHGUC, 96.6% for HGUC and 100.0% for NUM, respectively. ROHM of SHGUC was significantly higher than that of AUC group, and the difference between the two groups was statistically significant (P＜0.001). ROHM of HGUC group was significantly higher than that of SHGUC group, and the difference was statistically significant (P＜0.001). With SHGUC as the cut-off value, the sensitivity and specificity of cytological diagnosis of HGUC were 76.7% (165/215) and 85.7% (18/21), and with HGUC as the cut-off value, the sensitivity and specificity of cytological diagnosis of HGUC were 53.0% (114/215) and 100.0% (21/21), respectively. Conclusions: Urine cytology has high sensitivity and specificity in the diagnosis of HGUC. The malignant risk of TPS varies with different diagnosis category. The high malignant risk population in cancer hospital leads to the relatively high malignant proportion and ROHM in each diagnosis category. Urinary cytology TPS reporting system is helpful to clinical management and has good clinical application value.

Korean urobiome platform (KUROM) study for acute uncomplicated sporadic versus recurrent cystitis in women: Clinical significance.

PURPOSE: To investigate urine microbiome differences among healthy women, women with recurrent uncomplicated cystitis (rUC), and those with sporadic/single uncomplicated cystitis (sUC) to challenge traditional beliefs about origins of these infections. MATERIALS AND METHODS: Patients who underwent both conventional urine culture and next-generation sequencing (NGS) of urine were retrospectively reviewed. Symptom-free women with normal urinalysis results as a control group were also studied. Samples were collected via transurethral catheterization. RESULTS: In the control group, urine microbiome was detected on NGS in 83.3%, with Lactobacillus and Prevotella being the most abundant genera. The sensitivity of urine NGS was significantly higher than that of conventional urine culture in both the sUC group (91.2% vs. 32.4%) and the rUC group (82.4% vs. 16.4%). In urine NGS results, Enterobacterales, Prevotella, and Escherichia/Shigella were additionally found in the sUC group, while the recurrent urinary tract infection (rUTI)/rUC group exhibited the presence of Lactobacillus, Prevotella, Enterobacterales, Escherichia/Shigella, and Propionibacterium. Moreover, distinct patterns of urine NGS were observed based on menopausal status and ingestion of antibiotics or probiotics prior to NGS test sampling. CONCLUSIONS: Urine microbiomes in control, sUC, and rUTI/rUC groups exhibited distinct characteristics. Notably, sUC and rUC might represent entirely separate pathological processes, given their distinct urine microbiomes. Consequently, the use of urine NGS might be essential to enhancing sensitivity compared to conventional urine culture in both sUC and rUTI/rUC groups.

Presence of intracellular bacterial communities in uroepithelial cells, a potential reservoir in symptomatic and non-symptomatic people.

BACKGROUND: Urinary tract infection is one of the most common infections in humans, affecting women in more proportion. The bladder was considered sterile, but it has a urinary microbiome. Moreover, intracellular bacteria (IB) were observed in uroepithelial cells from children and women with urinary tract infections (UTIs). Here, we evaluated the presence of IB in urine from healthy people and patients with UTI symptoms. METHODS: Midstream urine was self-collected from 141 donors, 77 females and 64 males; 72 belonged to the asymptomatic group and 69 were symptomatic. IB was characterized by a culture-dependent technique and visualized by confocal microscopy. Urine was also subjected to the classical uroculture and isolated bacteria were identified by MALDI-TOF. RESULTS: One-hundred and fifteen uroculture were positive. A significant association was observed between the presence of symptoms and IB (P = 0.007). Moreover, a significant association between the presence of IB, symptoms and being female was observed (P = 0.03). From the cases with IB, Escherichia coli was the most frequent microorganism identified (34.7%), followed by Stenotrophomonas maltophilia (14.2%), Staphylococcus spp (14.2%), and Enterococcus faecalis (10.7%). Intracellular E. coli was associated with the symptomatic group (P = 0.02). Most of the intracellular Staphylococcus spp. were recovered from the asymptomatic group (P = 0.006). CONCLUSIONS: Intracellular bacteria are present in patients with UTI but also in asymptomatic people. Here, we report for the first time, the presence of S. maltophilia, Staphylococcus spp., and Enterobacter cloacae as intracellular bacteria in uroepithelial cells. These findings open new insights into the comprehension of urinary tract infections, urinary microbiome and future therapies. Uroculture as the gold standard could not be enough for an accurate diagnosis in recurrent or complicated cases.

[Urinary cytology for the detection of urothelial lesions]. / Rôle de la cytologie urinaire dans le dépistage des lésions urothéliales.

Urine cytology is a long-used technique for the detection of high grade neoplastic urothelial lesions. Since 2016, «The Paris System¼ classification has revolutionized this field by introducing a standardized terminology widely adopted by cytopathologists and urologists. In this article, we explain this classification and discuss its impact on the clinical management of patients with urothelial lesions, as well as its role in the secondary prevention of these lesions.

La cytologie urinaire est une technique utilisée depuis longtemps dans la détection des lésions urothéliales tumorales de haut grade. Depuis 2016, la classification «The Paris System¼ a révolutionné ce domaine en introduisant une terminologie standardisée largement adoptée par les cytopathologistes et les urologues. Dans cet article, nous expliquons cette classification et discutons de son impact sur la prise en charge clinique des lésions urothéliales, ainsi que son rôle dans la prévention secondaire de ces lésions.

Computer-assisted urine cytology: Faster, cheaper, better?

Recent advancements in computer-assisted diagnosis (CAD) have catalysed significant progress in pathology, particularly in the realm of urine cytopathology. This review synthesizes the latest developments and challenges in CAD for diagnosing urothelial carcinomas, addressing the limitations of traditional urinary cytology. Through a literature review, we identify and analyse CAD models and algorithms developed for urine cytopathology, highlighting their methodologies and performance metrics. We discuss the potential of CAD to improve diagnostic accuracy, efficiency and patient outcomes, emphasizing its role in streamlining workflow and reducing errors. Furthermore, CAD tools have shown potential in exploring pathological conditions, uncovering novel biomarkers and prognostic/predictive features previously unknown or unseen. Finally, we examine the practical issues surrounding the integration of CAD into clinical practice, including regulatory approval, validation and training for pathologists. Despite the promising results, challenges remain, necessitating further research and validation efforts. Overall, CAD presents a transformative opportunity to revolutionize diagnostic practices in urine cytopathology, paving the way for enhanced patient care and outcomes.

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.

Challenges of therapeutic applications and regenerative capacities of urine based stem cells in oral, and maxillofacial reconstruction.

Urine-derived stem cells (USCs) have gained the attention of researchers in the biomedical field in the past few years . Regarding the several varieties of cells that have been used for this purpose, USCs have demonstrated mesenchymal stem cell-like properties, such as differentiation and immunomodulation. Furthermore, they could be differentiated into several lineages. This is very interesting for regenerative techniques based on cell therapy. This review will embark on describing their separation, and profiling. We will specifically describe the USCs characteristics, in addition to their differentiation potential. Then, we will introduce and explore the primary uses of USCs. These involve thier utilization as a platform to produce stem cells, however, we shall concentrate on the utilization of USCs for therapeutic, and regenerative orofacial applications, providing an in-depth evaluation of this purpose. The final portion will address the limitations and challenges of their implementation in regenerative dentistry.

Longitudinal alterations in the urinary virome of kidney transplant recipients are influenced by BK viremia and patient sex.

Little is known about the urinary virome and how it interacts with the host, particularly in renal transplant diseases. Using metagenomic sequencing, we characterized the urinary virome of 23 kidney transplant recipients longitudinally (11 BKV+ patients and 12 BKV- patients). We applied linear mixed effects models, PERMANOVA, k-means clustering, and MaAsLin2 algorithms to determine virome signatures associated with post-transplant time, BK viremia status, and patient sex. We found that the richness and alpha diversity of urinary virome were significantly different in renal transplant recipients with BKV+ over time in comparison to BKV- (richness P = 0.012, alpha P < 0.0001). Female BKV- patients had significantly higher virome richness than males (P = 0.0063). Virome beta diversity was significantly different between patients by BKV status (P < 0.001). Additionally, we identified underlying interactions between patient sex and BKV status, in terms of virome beta diversity (P = 0.008). BK polyomavirus infections were primarily of subtypes IA, IB1, and IB2. The non-BK dominant samples clustered into six urinary virome community states. BKV- samples had more anelloviruses than BKV+ samples though this difference was not statistically significant. Lastly, we identified specific viruses, associated with BKV+ and time in our samples. Our results indicate that dynamic alterations in the urinary virome over the post-transplant period in kidney transplant recipients can be shaped by BK viremia and patient sex. These findings advance our fundamental understanding of the urinary virome and support a new line of investigation in renal disease and transplantation. IMPORTANCE: The urinary microbiome is increasingly implicated in renal health and disease. While most research focuses on bacteria communities of the microbiome, factors that influence the urinary virome are not understood. Here, we investigated the urinary virome of 23 adult kidney transplant recipients longitudinally over 14 weeks post-transplant. We show that alterations in the urinary virome are associated with kidney transplant recipients with BK polyomavirus viremia that can lead to BK nephropathy and allograft rejection. By modeling the temporal dynamics post-transplant, we delineated specific profiles of the urinary virome associated with patient sex and urinary community states. These findings reveal fundamental aspects of the urinary virome that can be leveraged to better manage kidney diseases.

Improved recovery of urinary small extracellular vesicles by differential ultracentrifugation.

Extracellular vesicles (EVs) are lipid-membrane enclosed structures that are associated with several diseases, including those of genitourinary tract. Urine contains EVs derived from urinary tract cells. Owing to its non-invasive collection, urine represents a promising source of biomarkers for genitourinary disorders, including cancer. The most used method for urinary EVs separation is differential ultracentrifugation (UC), but current protocols lead to a significant loss of EVs hampering its efficiency. Moreover, UC protocols are labor-intensive, further limiting clinical application. Herein, we sought to optimize an UC protocol, reducing the time spent and improving small EVs (SEVs) yield. By testing different ultracentrifugation times at 200,000g to pellet SEVs, we found that 48 min and 60 min enabled increased SEVs recovery compared to 25 min. A step for pelleting large EVs (LEVs) was also evaluated and compared with filtering of the urine supernatant. We found that urine supernatant filtering resulted in a 1.7-fold increase on SEVs recovery, whereas washing steps resulted in a 0.5 fold-decrease on SEVs yield. Globally, the optimized UC protocol was shown to be more time efficient, recovering higher numbers of SEVs than Exoquick-TC (EXO). Furthermore, the optimized UC protocol preserved RNA quality and quantity, while reducing SEVs separation time.

Efficacy of praziquantel drug against Schistosoma haematobium and performance of urine reagent strips among pre-and-school aged children during the high transmission season in North-Western Tanzania.

The World Health Organization calls for schistosomiasis endemic countries to regularly monitor the efficacy of Praziquantel (PZQ) drug, the only antischistosomal drug used for four decades in Tanzania. In response to that call, the current study investigated the efficacy of single dose of PZQ against Schistosoma haematobium during the high transmission season and further assessed, the sensitivity and specificity of urine reagent strips before and after treatment. The study recruited a total of 2,498 -children aged (4 -17 years old) who provided a single urine sample that was visually examined for macro-haematuria, then using urine dipstick and urine filtration technique for microhaematuria and the presence of S. haematobium eggs. The baseline prevalence of S. haematobium eggs positive based on urine filtration test was 29.2 % (95 %CI:27.5-31.0) and that of microhaematuria was 43.1 % (95 %CI:41.1-45.0). Of the infected participants, 40.9 % (95 %CI:37.4-44.6) had a heavy intensity of infection and the geometrical mean intensity (GMI) of infection was 33.7 eggs/10mls of urine. A single dose of PZQ reduced the prevalence of infection to 16.2 %, the GMI of infection to 18.8eggs/10mls of urine and that of microhaematuria to 27.9 %. Cure rate and egg reduction rates (ERR) were 83.8 % and 44.3 % respectively. At baseline, the sensitivity and specificity of the urine reagent strips were 59.7 % and 93.8 %, whereas at post-treatment they were 16.7 % and 93.6 %. When PZQ drug is administered during the high transmission season, its efficacy in term of ERR is poor. The urine reagent strips had low sensitivity but high specificity at pre-and-post PZQ treatment.

Correlation between urine cytology results on the day after overnight continuous saline irrigation following transurethral resection of bladder tumor and bladder tumor recurrence.

PURPOSE: To investigate the relationship between urine cytology results after overnight continuous saline irrigation (OCSI) following transurethral resection of bladder tumor (TURBT) and bladder tumor recurrence in non-muscle invasive bladder cancer (NMIBC). MATERIALS AND METHODS: A retrospective study was conducted on patients diagnosed with NMIBC between 2016 and 2020 after undergoing TURBT at our hospital. All patients received OCSI following TURBT and had urine cytology test at postoperative 1 day. Urine cytology was classified into three groups: Negative, low-grade urothelial neoplasm (LGUN)+atypical urothelial cells (AUC), and suspicious for high-grade urothelial carcinoma (SHGUC)+high-grade urothelial carcinoma (HGUC). Recurrence-free survival (RFS) in each group was compared using the Kaplan-Meier method. Univariable and multivariable Cox regression analyses were performed to evaluate independent prognostic factors. RESULTS: A total of 172 patients were included in this study. Based on urine cytology group (after OCSI), RFS did not reach the median value in the Negative group. In the LGUN+AUC group, the median RFS was 615.00 days. In the SHGUC+HGUC group, the median RFS was 377.00 days. In survival analysis, the Negative group had a longer RFS than the SHGUC+HGUC group (p=0.013). However, Cox regression analysis showed that SHGUC+HGUC was not an independent prognostic factor for recurrence. CONCLUSIONS: Urine cytology results after OCSI following TURBT in NMIBC were associated with bladder tumor recurrence. Specifically, SHGUC or HGUC in urine cytology after OCSI showed earlier recurrence than negative cases. However, further research is needed to accurately determine whether it is an independent prognostic factor.

Microfilaruria of Dirofilaria immitis in a dog from Italy.

Dirofilaria immitis is a mosquito-borne nematode-causing canine heartworm disease, with adult worms localized in the pulmonary arteries and right heart. In rare cases, ectopic migration might occur, and adults and blood circulating microfilariae can be found in unusual organs or fluids (e.g., eyes, abdominal cavity, bone marrow, and urine). A 17-year-old mixed-breed female dog was presented in a private veterinary clinic in Italy for hematuria and dysuria. Physical examination showed cardiac mitral murmur with marked respiratory distress and cyanotic mucous membranes after handling. Abdominal ultrasounds revealed a non-specific chronic cystopathy, while the echocardiography showed enlargement of the right heart associated with tricuspid insufficiency and mitral regurgitation, with the presence of an adult filariae in the right ventricular chamber. Circulating microfilariae were observed in the blood smear and molecularly identified as D. immitis. Unusual microfilaruria was detected in the urine sediment. Data presented raise awareness about the occurrence of microfilariae in unusual locations, such as the bladder, suggesting the need of a thorough clinical and laboratory assessment where D. immitis is endemic.

Voided urine cytology is a useful tool predicting non-muscle-invasive bladder cancer risk before surgery.

OBJECTIVE: To determine the accuracy of voided urinary cytology (VUC) in predicting of non-muscle-invasive bladder cancer (NMIBC) risk stratification before surgery. METHODS: We prospectively collected data from all patients diagnosed with bladder cancer in our institution over 2 years. We have analyzed VUC accuracy of positive and suspicious VUC in the detection of high-risk tumors and negative and atypical VUC in the detection of low-risk tumors. To test this accuracy, we assessed sensitivity, specificity, positive (PPV) and negative predictive values (NPV), diagnostic odds ratio (DOR), and generated ROC curves (receiver operating characteristic curve). RESULTS: With 224 patients included, the positive VUC subcategory showed a specificity of 92.4% (95%CI: 83.2%-97.5%) and a PPV of 91.4 (95%CI: 81%-97.1%). DOR in this subgroup was 6.81. In the suspicious VUC, specificity was 90.9% (95%CI: 81.3%-96.6%), PPV was 88% (95%CI: 75.7%-95.5%) and DOR was 4.23. Combined analysis of positive and suspicious cytologies for detecting high-risk NMIBC showed a sensitivity of 65% (95%CI: 57.3%-73.2%) and a DOR of 9.51. Negative VUC showed high specificity in detecting low-risk (93.2% [95%CI: 87.9%-96.7%]) and a DOR of 6.90 (95%CI: 3.07-15.46). Atypical VUC was the least accurate and had rather low specificity and predictive values. CONCLUSIONS: VUC appears to be a good, inexpensive and easily available method to determine risk stratification before surgery. This can be useful in daily practice to determine which patients should receive a single instillation of MMC and to prioritize patients more likely to have a high- risk tumor.

[Practical application of the Paris system for reporting urinary cytology].

Objective: To validate the diagnostic performance of the Paris system for reporting urinary cytology (TPS). Methods: A total of 7 046 urine cytology samples from 3 402 patients collected in the Department of Pathology, Beijing Hospital, China from January 2020 to January 2022 were analyzed. 488 patients had a biopsy or resection specimen during the follow-up period of 6 months. The sensitivity, specificity, risk of malignancy (ROM) and risk of high-grade malignancy (ROHM) of the TPS were evaluated using histological diagnosis as the golden standard. Results: Among the 7 046 samples, high-grade urothelial carcinoma (HGUC) accounted for 5.7% (399/7 046), suspicious for high-grade urothelial carcinoma (SHGUC) for 3.2% (227/7 046), atypical urothelial cells (AUC) for 8.4% (593/7 046), and negative for high-grade urothelial carcinoma (NHGUC) for 72.9% (5 139/7 046) including low-grade urothelial neoplasm (LGUN) for 0.8% (59/7 046) and insufficient samples for 9.8% (688/7 046). 488 patients had a bladder biopsy or resection in the follow-up of six months, including 314 males and 174 females, aged 27 to 92 years (average, 66 years). The ROHM of TPS was 94.7% in HGUC, 83.3% in SHGUC, 41.3% in AUC and 18.8% in NHGUC. The sensitivity and specificity of urine cytology were 70.1% (169/241) and 97.0% (162/167), respectively. The negative predictive value of NHGUC was 69.2% (162/234). Conclusions: The study has shown that TPS classification has high sensitivity and specificity, high ROHM for HGUC and SHGUC, and high negative predictive value for NHGUC. The application of TPS reporting system can better interpret the clinical significance of cytology samples, improve the accuracy of urine cytopathology and ensure continuous diagnostic consistency.

Renal B-lymphoblastic lymphoma with hematuria as the first symptom diagnosed in urine cytology: A case report and literature review.

Cytological examination of urine sediment is a helpful diagnostic tool for identifying renal involvement by hematological malignancies. We present the case of a 47-year-old man who was diagnosed with extranodal B-lymphoblastic lymphomas after presenting with gross hematuria as his first symptom. The presence of lymphoma cells in the urine led to a diagnosis confirmed through an immunophenotypic study using cell block sections of urine centrifuge sediment and core needle biopsy histology of the right renal pelvis mass. This case highlights the usefulness of a urine cytological study in diagnosing lymphoma involvement in the genitourinary tract. Furthermore, this paper reviews relevant literature on diagnosing lymphoma involvement from urine sediment.

Atypical squamous cells in urine cytology are associated with a significant risk of high-grade malignancy.

BACKGROUND: Atypical squamous cells (ASC) in urine cytology are rarely found, and their clinical significance is not well studied. Previous studies were limited by a small number of cases and a lack of objective grading of ASC and/or their correlation with accompanying urothelial cell abnormality (UCA). METHODS: The institutional database was searched over 10 years for urine cytology reports containing ASC or from patients who had a concurrent diagnoses of high-grade (HG) urothelial carcinoma with squamous differentiation or squamous carcinoma. ASC were defined as keratinized squamous cells and were subcategorized as reactive, koilocytosis, low-grade (LG) atypia, and HG atypia. Correlations with age, sex, specimen type, accompanying UCA, number of ASC, and the risk of HG malignancy (ROHM) were assessed. RESULTS: ASC were present in 0.15% of all urine specimens (123 of 81,018). Slides and clinical follow-up were available on 91 patients (median age, 71 years). LG and HG squamous atypia had ROHMs of 70% and 92%, respectively. ASC not accompanied and accompanied by UCA had ROHMs of 37% and 94%, respectively. Most malignancies (34 of 67; 51%) showed rare ASC in urine. Reactive changes and koilocytosis had 0% ROHM. CONCLUSIONS: ASC in urine cytology is a significant finding and is associated with a high ROHM. In the absence of accompanying UCA, LG squamous atypia had a lower ROHM than HG atypia. In the presence of UCA, LG and HG squamous atypia had ROHMs of over 90%. These findings suggest that ASC and their grade of atypia should be noted in the cytology report, and clinicians should be made aware of their clinical significance.

[What contribution can make artificial intelligence to urinary cytology?] / Quel apport de l'intelligence artificielle en cytologie urinaire ?

Urinary cytology using the Paris system is still the method of choice for screening high-grade urothelial carcinomas. However, the use of the objective criteria described in this terminology shows a lack of inter- and intra-observer reproducibility. Moreover, if its sensitivity is excellent on instrumented urine, it remains insufficient on voided urine samples. Urinary cytology appears to be an excellent model for the application of artificial intelligence to improve performance, since the objective criteria of the Paris system are defined at cellular level, and the resulting diagnostic approach is presented in a highly "algorithmic" way. Nevertheless, there is no commercially available morphological diagnostic aid, and very few predictive devices are still undergoing clinical validation. The analysis of different systems using artificial intelligence in urinary cytology rises clear prospects for mutual contributions.