KRT18 as a Novel Biomarker of Urothelial Papilloma while Evaluating Low-Grade Papillary Urothelial Neoplasms: Bi-Center Analysis.

INTRODUCTION: Although urothelial papilloma (UP) is an indolent papillary neoplasm that can mimic the morphology of low-grade papillary urothelial carcinoma (PUC), there is no immunomarker to differentiate reliably these two entities. In addition, the molecular characteristics of UP are not fully understood. METHODS: We conducted an in-depth proteomic analysis of papillary urothelial lesions (n = 31), including UP and PUC along with normal urothelium. Protein markers distinguishing UP and PUC were selected with machine learning analysis, followed by internal and external validation using immunohistochemistry. RESULTS: In the proteomic analysis, UP and PUC showed overlapping proteomic profiles. We identified EHD4 and KRT18 as candidate diagnostic biomarkers of UP. Through immunohistochemical validation in two independent cohorts (n = 120), KRT18 was suggested as a novel UP diagnostic marker, able to differentiate UP from low-grade PUC. We also found that 3.5% of patients with UP developed urothelial carcinoma in subsequent resections, supporting the malignant potential of UP. KRT18 downregulation was significantly associated with UPs subsequently progressing to urothelial carcinoma, following their initial diagnosis. CONCLUSION: This is the first study that successfully revealed UPs comprehensive proteomic landscape, while it also identified KRT18 as a potential diagnostic biomarker of UP.

Quantitative proteomics and immunohistochemistry uncover NT5DC2 as a diagnostic biomarker for papillary urothelial carcinoma.

The accurate diagnosis of papillary urothelial carcinoma (PUC) is frequently challenging due to benign mimickers. Other than morphology-based diagnostic criteria, reliable biomarkers for differentiating benign and malignant papillary urothelial neoplasms remain elusive, so we sought to discover new markers to address this challenge. We first performed tandem mass spectrometry-based quantitative proteomics using diverse papillary urothelial lesions, including PUC, urothelial papilloma (UP), inverted urothelial papilloma, and cystitis cystica. We prioritized potential diagnostic biomarkers using machine learning, and subsequently validated through immunohistochemistry (IHC) in two independent cohorts. Metabolism, transport, cell cycle, development, and immune response functions were differentially enriched between malignant and benign papillary neoplasms. RhoB and NT5DC2 were shortlisted as optimal candidate markers for PUC diagnosis. In our pilot study using IHC, NT5DC2 was subsequently selected as its expression consistently differed in PUC (p = 0.007). Further validation of NT5DC2 using 49 low-grade (LG) urothelial lesions, including 15 LG-PUCs and 17 UPs, which are the most common mimickers, concordantly revealed lower IHC expression levels in LG-PUC (p = 0.0298). Independent external validation with eight LG-PUCs and eight UPs confirmed the significant downregulation of NT5DC2 in LG-PUC (p = 0.0104). We suggest that NT5DC2 is a potential IHC biomarker for differentiating LG-PUC from its benign mimickers, especially UP.

Cytomorphological characteristics of low-grade papillary urothelial carcinoma in voided urine samples: Distinction from benign and high-grade papillary urothelial carcinoma.

OBJECTIVE: Given its frequent recurrence and the potential for high-grade transformation, accurate diagnosis of low-grade papillary urothelial carcinoma (LGPUC) in urine cytology is clinically important. We attempted to identify cytomorphologic features in urine samples, which could be helpful for the identification of LGPUC. METHODS: We conducted a retrospective review of voided urine specimens collected from patients with histopathologic diagnoses of LGPUC. Their cytomorphological features were compared with those from patients with benign conditions and high-grade papillary urothelial carcinoma (HGPUC). RESULTS: A total of 115 voided urine specimens were evaluated, including 30 benign, 41 LGPUC, and 44 HGPUC cases. In LGPUC, 18 cases (44%) were diagnosed as atypical, a proportion significantly higher than that observed in benign cases (4 cases, 13%), while the remaining 23 cases (56%) were diagnosed as negative. LGPUC urine samples tended to have higher cellularity than benign cases, but the difference was not statistically significant. Three cytological features, namely nuclear enlargement, higher nuclear-to-cytoplasmic (N/C) ratio, and presence of small cell clusters, were statistically more prevalent in LGPUC compared to benign cases, although the changes were relatively subtle. In contrast, cytomorphological distinction between LGPUC and HGPUC was evident, as high cellularity, nuclear enlargement, hyperchromasia, high N/C ratio, irregular nuclear membrane, and apoptosis were significantly more prevalent in HGPUC cases. CONCLUSIONS: Several cytomorphologic features in voided urine samples were more prevalent in cases with LGPUC, albeit not observed in all instances. Since these alterations were relatively subtle, meticulous attention to these cytomorphologic details is crucial to suggest the possibility of LGPUC.

Challenges and technical aspects in the management of muscle invasive bladder cancer as retrograde radical cystectomy with ileal conduit.

Objective: To evaluate long-term outcomes in patients homogenously treated with radical cystectomy and ileal conduit for muscle invasive bladder cancer. METHODS: The retrospective study was conducted at the Urology Department of Pakistan Kidney and Liver Institute and Research Centre, Lahore, Pakistan, and comprised data from December 25, 2017, to January 16, 2023, related to patients who underwent radical cystectomy with ileal conduit with or without neo-adjuvant and adjuvant radiation, chemotherapy, or immunotherapy for papillary urothelial carcinom of the bladder. Clinical trajectory, histopathological characteristics and long-term clinical outcomes were noted. Data was analysed using SPSS 20. RESULTS: In our study of 40 patients with muscle invasive bladder cancer, males predominated (32, 80%), with a median age of 57.4 years (IQR: 29-80). Diagnosis was early in 5 (12.5%) patients with varying haematuria durations, while 34 (85%) patients had a smoking history. Comorbidities included hypertension in 17 (42.5%) patients, diabetes in 1 (2.5%) patient, both hypertension and diabetes in 9 (22.5%) patients and a combination of hypertension, diabetes, and ischaemic heart disease in 3 (7.5%) patients. Transurethral resection was performed once in 13 (32.5%) patients and multiple times in 27 (67.5%) patients. Additionally, 5 (12.5%) patients received immunotherapy, 11 (27.5%) patients underwent non-adjuvant radiation, and 14 (35%) patients received non-adjuvant chemotherapy. Papillary urothelial carcinoma was the predominant histological subtype among 37 (92.5%) patients. Patients receiving chemotherapy had significantly better overall survival (p=0.02). No significant differences were noted in recurrence or survival by therapy modality (p>0.05). These findings highlight the significance of early diagnosis, tailored treatments, and comorbidity management in muscle invasive bladder cancer patients. Age stratification revealed significant survival differences across groups (χ²=10.923, df=3, p= 0.012). Analysis by complications did not show age-related survival variations (χ² =3.978, df = 3, p=0.264). Conclusion: Achieving excellent long-term survival in MIBC patients requires a multidisciplinary approach, emphasizing early diagnosis, tailored treatment, and adherence to guidelines and protocols.

Urinary Bladder Cancer Induced by N-Butyl-N-(4-Hydroxybutyl)-Nitrosamine.

Urinary bladder cancer is the tenth most common cancer worldwide with high morbidity and mortality. The majority of bladder cancers are urothelial carcinomas. More than half are papillomas or the papillary urothelial carcinomas (stages Ta and T1), which have a relatively good prognosis. Squamous cell carcinomas have a variable survival rate, while carcinomas in situ (Tis) can progress to muscle-invasive urothelial carcinomas (T2) with a poor prognosis. The most challenging feature of bladder cancer is its high recurrence rate, ranging from 50% to 90% of cases. The N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) model is an invaluable experimental tool for bladder cancer research, as BBN-induced bladder cancer in rodents resembles human bladder cancer in its morphological, biological, and molecular features. We present here a detailed protocol for the treatment of mice and the main expected results.

Synchronous Penile Squamous Cell Carcinoma, Bladder Urothelial Carcinoma and Prostate Adenocarcinoma Diagnosed in One Procedure.

BACKGROUND: The synchronous diagnoses of three primary malignancies in a patient is rare and represents a difficult treatment challenge. We report a rare case of an 81-year-old male with synchronous triple urogenital cancers including penile squamous cell carcinoma, bladder papillary urothelial carcinoma, and prostate adenocarcinoma. CASE REPORT: The patients presented with a penile lesion with blood draining through the foreskin. Further examination with cystoscopy during the biopsy procedure revealed a 1.5-cm tumor along the left lateral bladder wall and a firm prostate in bilateral lobes. Diagnosis of penile squamous cell carcinoma was confirmed by biopsies of the penile lesions and glans as confirmed by cystoscopy and histological evaluation of the tissue obtained by transurethral resection of the bladder. Biopsies of the prostatic urethra confirmed a diagnosis of prostate adenocarcinoma. All biopsies were performed in a single procedure. Pathology findings revealed moderately differentiated squamous cell carcinoma (p16+) invading the lamina propria of the glans penis, noninvasive low-grade papillary urothelial carcinoma of the bladder, and high-grade prostatic adenocarcinoma (Gleason score 5+5=10) within the prostatic stroma. CONCLUSION: Review of the English literature through PubMed search suggests that this specific combination of synchronous triple urogenital cancer is the first documented case of its kind. Incidence, diagnosis, and treatment for the combination of these cancer types are discussed with consideration for concurrent management of three primary cancers.

Multiparametric Classification of Non-Muscle Invasive Papillary Urothelial Neoplasms: Combining Morphological, Phenotypical, and Molecular Features for Improved Risk Stratification.

Diagnosis and grading of non-invasive papillary urothelial tumors according to the current WHO classification poses some challenges for pathologists. The diagnostic reproducibility of separating low-grade and high-grade lesions is low, which impacts their clinical management. Whereas papillary urothelial neoplasms with low malignant potential (PUN-LMP) and low-grade papillary non-invasive carcinoma (LG-PUC) are comparable and show frequent local recurrence but rarely metastasize, high-grade papillary non-invasive carcinoma (HG-PUC) has a poor prognosis. The main objective of this work is to develop a multiparametric classification to unambiguously distinguish low-grade and high-grade tumors, considering immunohistochemical stains for p53, FGFR3, CK20, MIB-1, p16, p21 and p-HH3, and pathogenic mutations in TP53, FGFR3, TP53, ERCC2, PIK3CA, PTEN and STAG2. We reviewed and analyzed the clinical and histological data of 45 patients with a consensus diagnosis of PUN-LMP (n = 8), non-invasive LG-PUC (n = 23), and HG-PUC (n = 14). The proliferation index and mitotic count assessed with MIB-1 and P-HH3 staining, respectively correlated with grading and clinical behavior. Targeted sequencing confirmed frequent FGFR3 mutations in non-invasive papillary tumors and identified mutations in TP53 as high-risk. Cluster analysis of the different immunohistochemical and molecular parameters allowed a clear separation in two different clusters: cluster 1 corresponding to PUN-LMP and LG-PUC (low MIB-1 and mitotic count/FGFR3 and STAG2 mutations) and cluster 2, HG-PUC (high MIB-1 and mitosis count/CK20 +++ expression, FGFR3 WT and TP53 mutation). Further analysis is required to validate and analyze the reproducibility of these clusters and their biological and clinical implication.

Proteomic-Based Machine Learning Analysis Reveals PYGB as a Novel Immunohistochemical Biomarker to Distinguish Inverted Urothelial Papilloma From Low-Grade Papillary Urothelial Carcinoma With Inverted Growth.

Background: The molecular biology of inverted urothelial papilloma (IUP) as a precursor disease of urothelial carcinoma is poorly understood. Furthermore, the overlapping histology between IUP and papillary urothelial carcinoma (PUC) with inverted growth is a diagnostic pitfall leading to frequent misdiagnoses. Methods: To identify the oncologic significance of IUP and discover a novel biomarker for its diagnosis, we employed mass spectrometry-based proteomic analysis of IUP, PUC, and normal urothelium (NU). Machine learning analysis shortlisted candidate proteins, while subsequent immunohistochemical validation was performed in an independent sample cohort. Results: From the overall proteomic landscape, we found divergent 'NU-like' (low-risk) and 'PUC-like' (high-risk) signatures in IUP. The latter were characterized by altered metabolism, biosynthesis, and cell-cell interaction functions, indicating oncologic significance. Further machine learning-based analysis revealed SERPINH1, PKP2, and PYGB as potential diagnostic biomarkers discriminating IUP from PUC. The immunohistochemical validation confirmed PYGB as a specific biomarker to distinguish between IUP and PUC with inverted growth. Conclusion: In conclusion, we suggest PYGB as a promising immunohistochemical marker for IUP diagnosis in routine practice.

Sintilimab treatment for ureteral carcinoma following bladder cancer leads to leukopenia: a case report.

Herein, we present a case report of sintilimab treatment for a patient with ureteral cancer reoccurring after bladder cancer, and exploration of the mechanism of adverse reactions from the aspects of intestinal flora and immunity. We have reported a case of leukopenia in a patient with recurrent ureteral cancer after bladder cancer who was treated with sintilimab. A 52-year-old Chinese man with a history of hypertension and diabetes presented with lower urinary tract symptoms, including painless hematuria, frequent and urgent urination, and micturition without pain. Computed tomography (CT) and 3-dimensional (3D) reconstruction suggested bladder space occupation, bladder cancer was pathologically confirmed after laser resection of the bladder tumor, which then recurred and was subject to reoperation. After 8 months, B-mode ultrasonography indicated left ureter occupation, and the patient began sintilimab immunotherapy according to the outcome of immunohistochemistry (IHC) and immune checkpoint inhibitor (ICI) evaluation. The patient was treated with sintilimab a total of 6 times. After the first treatment, the patient was in stable condition. The second treatment was discontinued due to renal insufficiency. The patient was then treated with renal and liver protection for 1.5 months, followed by 5 rounds of immunotherapy. After the sixth round of immunotherapy, the patient presented with leukopenia. In order to determine the causes of adverse reactions, we analyzed the changes of intestinal flora of patients before and after immunotherapy, and summarized the immune function indicators of patients during immunotherapy. The leucopenia induced by sintilimab may be related to intestinal flora and immunity.

Utility of GATA-3 and Cytokeratin 5/6 Immunostains in Separating Condyloma Acuminatum Arising in the Urinary Tract From Non-Invasive Papillary Urothelial Carcinoma.

Background Condyloma acuminatum is a squamous epithelial lesion which uncommonly involves the urinary tract. In this location, non-invasive papillary urothelial carcinoma constitutes one of the main differential diagnoses with significant prognostic and therapeutic implications. To date, no ancillary immunohistochemical stain has been described to differentiate these two entities. We assess the utility of cytokeratin 5/6 (CK5/6) and GATA-3 immunohistochemistry in distinguishing condyloma acuminatum from non-invasive papillary urothelial carcinoma. Design We reviewed 9 condylomata acuminata involving the urinary tract, 12 low-grade and 8 high-grade non-invasive papillary urothelial carcinomas. CK5/6 immunostaining was performed in all cases. GATA-3 immunostaining and low-risk human papilloma virus (HPV) chromogenic in situ hybridization was performed in all condyloma cases and 2 urothelial carcinomas with squamous differentiation. Results 8/9 condylomata acuminata were positive for low-risk HPV. All condylomata acuminata exhibited strong full-thickness cytoplasmic staining for CK5/6. In 10 of 12 low-grade non-invasive papillary urothelial carcinomas, CK5/6 expression was continuous and limited to the basal cell layer, while it was patchy and limited to the basal cell layer in all 8 high-grade non-invasive papillary urothelial carcinomas. Two low-grade non-invasive papillary urothelial carcinomas showed focal full-thickness CK5/6 expression in the areas of squamous differentiation. These 2 cases were negative for low-risk HPV. GATA-3 immunostaining was positive in all condylomata acuminata. Conclusions CK5/6 immunostaining is a useful and simple tool that can help separate low-grade and high-grade non-invasive papillary urothelial carcinomas from condyloma acuminatum involving the urothelium-lined organs. GATA-3 has no discriminatory role between condyloma acuminatum and papillary urothelial carcinomas.

Urothelial carcinoma of the graft kidney with molecular analyses: a rare case report.

BACKGROUND: Malignancy after transplantation is a leading cause of death among kidney transplant recipients. However, donor-derived malignancies are rare. We report a case of a high grade papillary urothelial carcinoma arising in a transplanted kidney. CASE PRESENTATION: A 62-year-old female who received a kidney transplantation more than 30 years ago presented with urinary tract infection, acute renal failure, and hydronephrosis of the transplant kidney. Anterograde nephrostogram showed a large filling defect in the lower pole of the transplant kidney and in the proximal 3-4 cm of the ureter. A biopsy from the renal pelvic mass showed a high grade urothelial carcinoma. She underwent an anterior exenteration, resection of both transplant and native kidneys and bilateral pelvic lymph node dissection. Pathologic examination showed a high grade papillary urothelial carcinoma which appeared to arise in the pelvis of the graft kidney, involve the graft ureter and native urinary bladder. The tumor had metastasized to one left obturator lymph node but spared the two native kidneys and ureters. Short tandem repeat (STR) analysis confirmed the tumor to be of donor origin. Next-generation sequencing identified amplification of TERT and loss of CDKN2A/CDKN2B in the primary tumor. CONCLUSION: While it is known that transplant recipients have an increased risk of urothelial carcinoma compared to the general population, the lack of the well-documented risk factors, such as older age at transplantation, BK polyomavirus infection, and prolonged post-transplantation history and dissemination of the tumor in this case shed light on the de novo tumorigenesis of the graft kidney within the host microenvironment. Amplification of Telomerase reverse transcriptase (TERT) and loss of cyclin dependent kinase inhibitor 2A/2B (CDKN2A/CDKN2B) detected in the tumor by next gene sequencing suggests that they may play an important role in this case.

Noninvasive low-grade papillary urothelial carcinoma with degenerative nuclear atypia: a grading pitfall.

Noninvasive low-grade papillary urothelial carcinoma is a papillary neoplasm with orderly appearance and mild nuclear pleomorphism. Some cases show significant nuclear pleomorphism with degenerative atypia leading to grading difficulties. A retrospective review of the pathology files identified 16 cases diagnosed as noninvasive low-grade papillary urothelial carcinoma with degenerative atypia. Fifteen cases were consults. The average age was 46 years (range 19-78). The average size was 1.7 cm (range: 0.3-3.5). The submitting diagnoses in consults were noninvasive high-grade papillary urothelial carcinoma (n = 6), condyloma (n = 1), atypical papillary lesion (n = 1), prominent umbrella cells (n = 1), and not given (n = 6). Ki-67 proliferation rate was <5% in 10 of 10 cases (100%), and the cells with large atypical nuclei were negative. Microscopically, there were scattered cells with nuclei larger than 5 times the size of stromal lymphocytes but displayed smudgy chromatin and occasional multinucleation and intranuclear vacuoles. Next-generation sequencing identified the following mutations: HRAS (n = 4), FGFR3 (n = 3), KRAS (n = 3), BRAF (n = 1), PDGFRA (n = 1), and PIK3CA (n = 1). Other deleterious mutations were identified, but none in genes characteristic of high-grade tumors. Follow-up was available in 6 patients (median 32 months). One patient recurred with a noninvasive low-grade papillary urothelial carcinoma 20 months after the index case. All the remaining patients had no evidence of disease at the last follow-up. No patient died or had disease progression. The combination of preservation of polarity, low mitotic activity, Ki-67 <5% with the larger atypical nuclei negative for Ki-67, along with nuclear atypia that is degenerative are features used to classify these tumors as low grade.

Microtubule-organizing center-mediated structural atypia in low- and high-grade urothelial carcinoma.

Urothelial carcinoma (UC) comprises two subtypes, low grade (LG-UC) and high grade (HG-UC), with different pathological and clinical behavior. LG-UC and HG-UC are classified based on cellular and structural atypia of pathological findings. The mechanisms responsible for maintaining structural atypia, such as the disturbance of nuclear polarity, remain unclear. In this study, we studied microtubule-organizing center (MTOC)-mediated nuclear polarity in UC subtypes. We evaluated six cases with normal urothelium (NU), 10 LG-UC cases, and 10 HG-UC cases by double immunofluorescence staining of γ-tubulin as a marker of MTOC and E-cadherin as a marker of each cell border. The number and position of γ-tubulin dots of expression in more than 100 cells per case were assessed using the spatial relationship with the nucleus and surface-basal axis. We found one γ-tubulin dot in most normal and tumor cells, and more than two γ-tubulin dots in 4.6% of NU cells, 6.1% of LG-UC cells, and 9.8% of HG-UC cells. More than three γ-tubulin dots were found only in 1.2% of HG-UC cells. Surface side positioning of γ-tubulin was found in 77.4% of normal urothelial cells, 63.8% of LG-UC cells, and 39.2% of HG-UC cells, whereas aberrant lateral and basal side positioning of γ-tubulin was found in 22.6% of normal urothelial cells, 36.1% of LG-UC cells, and 60.8% of HG-UC cells. We concluded that numerical and positional aberrations of MTOC in UC cases were strongly correlated with both cellular and structural atypia as well as abnormal cell proliferation.

Androgen Receptor: Evaluation and Correlation with Recurrence and Clinicopathological Parameters in Papillary Urothelial Carcinomas of the Urinary Bladder.

Papillary urothelial carcinoma (PUC) is the most common malignant tumor of the urinary bladder. Urothelial tumors are notorious for frequent recurrences and follow a chronic relapsing course in most of the patients. In Pakistan, the incidence of PUC is showing a rising trend. Various immunohistochemical (IHC) markers including androgens have been studied as prognostic and predictive markers in PUC with conflicting results. Androgen is a steroid-based sex hormone and plays an important role in different body organs such as urinary bladder, prostate, muscles, and brain. We aimed to investigate the role of the IHC expression of androgen receptor (AR) as a predictor of recurrence in papillary urothelial carcinoma patients. Eighty-four patients were included in the study. Tissues from the biopsy specimens of these cases were stained with antibodies against AR; 17% of the cases demonstrated a positive AR IHC expression. The expression was slightly more common in low-grade carcinoma. The AR expression was not significantly associated with clinicopathological features. Recurrence was observed in 49% of the cases, and it was significantly more common in AR-negative cases (p-value: 0.025). Eighteen out of 19 patients who died of disease were AR- negative, but no statistical significance was observed. We conclude that the IHC expression of AR can be used as a predictive marker for PUC as it correlates with the recurrence rate.

[Novel approaches for transurethral en-bloc resection of large bladder tumors].

OBJECTIVE: to develop optimal techniques of en-bloc resection of large non-muscle invasive bladder tumors, determine the proper method of specimen extraction and assess the quality of specimens obtained by different techniques. MATERIALS AND METHODS: A total of 12 patients with primary cT1 bladder cancer underwent transurethral en-bloc resection between January 2018 and March 2019 were enrolled into the study. Tumor size ranged from 3.5 cm to 6.2 cm. For removal and extraction of large bladder tumors using thulium fiber en-bloc laser three different techniques were developed: "swiss cheese technique", "crown and root technique" and "three steps technique" technique". The main pathologic criteria used for assessment of removal technique were tumor grade (G), depth of invasion (T), presence of carcinoma in situ (CIS), variant histology (VH), lymphovascular invasion (LVI), presence of detrusor muscle. Additional criteria were horizontal and vertical resection margin, subclassification of T1-stage and presence of focal necrosis in tumor. RESULTS: Among the techniques developed and tested, the best quality of specimens for morphological evaluation was obtained using the combined "crown and root technique". First step is electroresection of the exophytic part of the tumor into pieces, and the next step is en-bloc laser resection (using thulium fiber or holmium laser) of the tumor base. Overall, the quality of all specimens obtained using three techniques met the current requirements of pathologic study. SUMMARY: En-bloc resection techniques of large bladder tumors allow obtaining specimen suitable for proper morphological evaluation and correct tumor staging. Further studies are required to evaluate the impact of these techniques on long-term results of treatment options.

Prognostic value and reproducibility of different microscopic characteristics in the WHO grading systems for pTa and pT1 urinary bladder urothelial carcinomas.

BACKGROUND: European treatment guidelines for pTa and pT1 urinary bladder urothelial carcinoma depend highly on stage and WHO-grade. Both the WHO73 and the WHO04 grading systems show some intra- and interobserver variability. The current pilot study investigates which histopathological features are especially sensitive for this undesired lack of reproducibility and the influence on prognostic value. METHODS: Thirty-eight cases of primary non-muscle invasive urothelial carcinomas, including thirteen cases with stage progression, were reviewed by three pathologists. Thirteen microscopic features were extracted from pathology textbooks and evaluated separately. Reproducibility was measured using Gwet's agreement coefficients. Prognostic ability regarding progression was estimated by the area under curve (AUC) of the receiver operating characteristics (ROC) function. RESULTS: The best reproducible features (Gwet's agreement coefficient above 0.60) were papillary architecture, nuclear polarity, cellular maturation, nuclear enlargement and giant nuclei. Nucleoli was the strongest prognostic feature, and the only feature with an AUC above 0.70 for both grading systems, but reproducibility was not among the strongest. Nuclear polarity also had prognostic value with an AUC of 0.70 and 0.67 for the WHO73 and WHO04, respectively. The other features did not have significant prognostic value. CONCLUSIONS: The reproducibility of the histopathological features of the different WHO grading systems varied considerably. Of all the features evaluated, only nuclear polarity was both prognostic and significantly reproducible. Further validation studies are needed on these features to improve grading of urothelial carcinomas.

Transcriptional Analysis of Immunohistochemically Defined Subgroups of Non-Muscle-Invasive Papillary High-Grade Upper Tract Urothelial Carcinoma.

Immunohistochemical (IHC) staining for CK5/6 and CK20 was reported to be correlated with the prognosis of early urothelial carcinoma in a way contrary to that of advanced tumors for unknown reasons. We aimed to characterize the gene expression profiles of subgroups of non-muscle-invasive papillary high-grade upper tract urothelial carcinoma (UTUC) classified by CK5/6 and CK20 expression levels: group 1 (CK5/6-high/CK20-low), group 2 (CK5/6-high/CK20-high), and group 3 (CK5/6-low/CK20-high). Expression of group 3 was predictive of worse prognosis of non-muscle-invasive papillary high-grade UTUC. Transcriptional analysis revealed 308 differentially expressed genes across the subgroups. Functional analyses of the genes identified cell adhesion as a common process differentially enriched in group 3 compared to the other groups, which could explain its high-risk phenotype. Late cell cycle/proliferation signatures were also enriched in group 3 and in some of the other groups, which may be used as a prognostic biomarker complementary to CK5/6 and CK20. Group 2, characterized by low levels of genes associated with mitogen-activated protein kinase and tumor necrosis factor signaling pathways, was hypothesized to represent the least cancerous subtype considering its normal urothelium-like IHC pattern. This study would facilitate the application of easily accessible prognostic biomarkers in practice.

High Grade T1 Papillary Urothelial Bladder Cancer Shows Prominent Peritumoral Retraction Clefting.

Differentiation of noninvasive from invasive papillary urothelial carcinoma can be challenging due to inability of proper orientation and thermal damage of transurethrally obtained material. The aim of this study was to analyze the presence and extent of peritumoral retractions in pT1 compared to pTa papillary urothelial carcinoma. Since peritumoral retractions may result from altered expression profiles of extracellular matrix proteins, we additionally analyzed the expression of matrix metalloproteinase 2 (MMP-2) and interleukin 8 (IL-8) in these tumors. The study comprised 50 noninvasive (pTa) and 50 invasive (pT1) cases of transurethrally obtained primary papillary urothelial carcinomas. The invasive nature of nests showing peritumoral retractions was confirmed immunohistochemically using antibody against collagen IV. Staining for MMP-2 and IL-8 was evaluated semiquantitatively using immunohistochemical staining index, calculated by multiplying the percentage of positive cells and staining intensity. Peritumoral retractions were found in 32% of pT1 carcinomas but in none of the pTa carcinomas. All tumors showing peritumoral retraction were high grade tumors. There was no statistically significant correlation between the expression of MMP-2 or IL-8 and the presence of peritumoral retractions or stage of the tumor (pTa vs. pT1). A statistically significant but weak correlation was found between MMP-2 and IL-8 expression (χ2-test, p=0,015). There was no statistically significant correlation between the presence of peritumoral retractions or MMP-2 expression and tumor recurrence and progression. Our study shows that, in doubtful cases, when differentiating between pTa and pT1 stages of papillary urothelial carcinoma, the presence of peritumoral retractions could favor the diagnosis of invasive neoplasm.

Papillary Urothelial Neoplasm of Low Malignant Potential (PUNLMP) After Initial TUR-BT: Comparative Analyses with Noninvasive Low-Grade Papillary Urothelial Carcinoma (LGPUC).

Purpose: To verify if the distinction between papillary urothelial neoplasm of low malignant potential (PUNLMP) and noninvasive low-grade papillary urothelial carcinoma (LGPUC) reflects a different biologic activity. Materials and Methods: We reviewed and analyzed the clinical data from 678 patients who had a diagnosis of PUNLMP (n=53) or noninvasive LGPUC (n=625) after initial TUR-BT for bladder neoplasm between 2000 and 2012. Results: The noninvasive LGPUC group showed a higher frequency of recurrence in comparison with the PUNLMP group (46.7% vs. 30.2%, p=0.022). In contrast, there were no significant differences in progression (15.2% vs. 18.9%, p=0.295) between the two groups. Grade progression was reported in 10 patients (LG: n=5; high grade: n=2; carcinoma in situ: n=3) and stage progression was reported in 2 patients (all: T1) in PUNLMP group. The Kaplan-Meier survival analysis showed significantly decreased 5-year recurrence-free survival (RFS) (50.3% vs. 74.6%, log-rank test, p=0.014) in the noninvasive LGPUC group compared to the PUNLMP group. However, there were no significant differences in progression-free survival (PFS) between the two groups. Multivariate analysis revealed that tumor grades according to 2004 WHO/ISUP classification system (PUNLMP vs. LG) were identified as significant predictors of RFS. However, it was not a significant predictor of both PFS and overall survival. Conclusions: PUNLMP had a substantial number of recurrences (30.2%), although RFS was better than noninvasive LGPUC. In addition, PUNLMP had a similar risk of progression compared with noninvasive LGPUC. Consequently, PUNLMP should be treated in a manner similar to noninvasive LGPUC, and long-term clinical follow-up should be recommended for patients with PUNLMP.

Seeding of a high-grade papillary urothelial carcinoma of the bladder along a nephroureterostomy tract.

Percutaneous nephrostomy placement is a common treatment for obstructive uropathy of various causes. Although rare in the literature, tumor seeding along the nephrostomy tract is a potential risk of percutaneous nephrostomy in the treatment of obstructive symptoms secondary to urothelial carcinoma. In this case report, we present one such unusual outcome where urinary bladder urothelial cancer cells metastasized to the paravertebral soft tissues through apparent seeding along a nephroureterostomy tract.