Lymphoepithelioma-like, a variant of urothelial carcinoma of the urinary bladder: a case report and systematic review for optimal treatment modality for disease-free survival

The association between variant histology and prognostic, histomorphological and clinical aspects of bladder urothelial carcinoma

This study underscores the imperative consideration of histological subtypes and divergent differentiation in accurately estimating bladder urothelial carcinoma prognosis and guiding treatment decisions. A comparative analysis was conducted, examining clinical, histological, and prognostic factors between conventional urothelial carcinoma and urothelial carcinoma with variant histology in a clinical sample. A retrospective analysis of slides and other clinicopathologic data was conducted these cases, with an emphasis on key diagnostic elements. We examined 829 cases of urothelial carcinoma of the bladder, comprising of 744 transurethral resection (TUR) and 85 radical cystectomy (RS) specimens, an analysis that showed that 80.5 % (667 cases) were conventional urothelial carcinoma (CUC) and that 19.5 % (162 cases) exhibited variant histology (hereafter "urothelial carcinoma with subtype histology" [UCSH]). TNM classifications for the RS cases were as follows: 2 cases were stage group 0a, 11 stage group 1, 16 stage group 2, 45 stage group 3a, 2 stage group 3b, 1 stage group 4a, and 8 stage group 4b. Only 2 of the RS cases were found to be non-invasive. Among 744 TUR specimens, 387 were found to have a non-invasive tumor whereas 357 had invasive tumors. The most prevalent subtype in the UCSH group was urothelial carcinoma with squamous differentiation, accounting for 54.3 % (88 cases). Notably, 8.02 % (13 cases) exhibited more than one histological subtype. Papillary configuration, histological grade, lamina propria, muscularis mucosa and serosa invasion, lymphovascular invasion, presence of urothelial carcinoma in situ, and overall survival significantly differed between the UCSH and CUC groups (p < 0.05). However, mean age, gender, tumor size, lymphocytic response, disease-free survival, and survival status did not differ significantly (p > 0.05). Among the UCSH group, lower levels of papillary configuration, higher histological grade, higher degree of lamina propria, muscularis mucosa and serosa invasion, and the presence of carcinoma in situ corresponded to higher percentage of histological subtype morphology (p < 0.05). No significant difference in survival status was observed between the groups with and without subtype histology (p = 0.083). This study found that clinical and histopathological prognostic factors associated with a more aggressive disease were linked to the presence and percentage of histological subtypes. Recognizing histological subtype is crucial for treatment decisions and prognosis prediction in urothelial carcinoma cases with these subtypes.

Histopathologic, Molecular, and Clinical Profiling of Lymphoepithelioma-like Carcinoma of the Bladder

Lymphoepithelioma-like carcinoma of the bladder (LELC-B) is a rare histologic subtype characterized by strong immune cell (IC) infiltrates. A better prognosis and favorable response rates to immune checkpoint inhibitors have been described. We aimed to characterize the molecular profiles and IC infiltration of LELC-B for a better understanding of its therapeutic implications. We identified 11 muscle-invasive bladder cancer cases with pure and mixed LELC-B. Programmed cell death ligand-1 (PD-L1) expression and mismatch repair proteins were evaluated using immunohistochemistry. We calculated the tumor mutational burden and characterized mutational profiles using whole-exome DNA sequencing data. Transcriptomic signatures were detected using the NanoString nCounter PanCancer IO360 Panel. Multiplex immunofluorescence of tumor microenvironment (PD-L1, PanCK, α-SMA, vimentin, CD45, and Ki67) and T cells (CD4, CD3, PD-1, CD163, CD8, and FoxP3) was used to quantify cell populations. All LELC-B cases were highly positive for PD-L1 (median tumor proportion score/tumor cell, 70%; range, 20%-100%; median combined positive score, 100; range, 50-100) and mismatch repair proficient and negative for Epstein-Barr virus infection. IC infiltrates were characterized by a high CD8+ T-cell count and high PD-1/PD-L1 expression on immune and tumor cells. LELC-B showed upregulation of signaling pathways involved in IC response. Most common mutations were found in chromatin remodeling genes causing epigenetic dysregulation. All LELC-B cases showed high tumor mutational burden with a median of 39 mutations/Mb (IQR, 29-66 mutations/Mb). In conclusion, LELC-B is a highly immunogenic tumor, showing strong upregulation of PD-1/PD-L1 and making immune checkpoint inhibitors a promising treatment option.

Contrast-enhanced CT and PET-CT characteristics of primary tracheal lymphoepithelioma-like carcinoma: case series

Background

Primary tracheal lymphoepithelioma-like carcinoma (LELC) is extremely rare, with only a few cases reported so far, and few studies have focused on the radiological features. This study aimed to investigate contrast-enhanced computed tomography (CECT) and positron emission tomography-computed tomography (PET-CT) presentations of primary tracheal LELC to improve diagnosis.

Methods

A retrospective analysis was conducted on the clinical and imaging data of 13 patients with confirmed primary tracheal LELC between December 2013 and August 2022. We analyzed the radiological profiles of lesions on the CECT and PET-CT images.

Results

In 92.3% (12/13) of the cases, primary tracheal LELC lesions predominantly occurred in the thoracic segment. They manifested as singular, wide-based, eccentric, irregular nodules, or exhibited mass-like thickening of the tracheal wall with invasive growth both internally and externally along the wall. The thickest dimension of the lesion ranged from 9 to 28 mm, affecting a length of 30.8±13.5 mm. Luminal stenosis was evident in all patients, with the narrowest point reaching a stenosis rate of 85%. Lesion margins were clear in 69.2% (9/13), indistinct in 23.1% (3/13), and unclear in 7.7% (1/13) of all cases. Among the patients, 92.3% (12/13) exhibited a relatively uniform density on CT plain scans, with a CT value of 44.5±7.8 Hounsfield units (HU). Enhancement scans revealed moderate to marked enhancement in 75% (9/12) of cases. In 2 cases undergoing PET-CT examination, lesion standardized uptake values (SUVs) were 4.4 and 5.1, whereas enlarged lymph node SUVs were 7.7 and 6.3, respectively. Mediastinal lymph node enlargement was observed in 8 patients (61.5%, 8/13), with a maximum short axis of 11.1±5.5 mm. After treatment, 9 out of 12 patients (75%) showed no evidence of distant metastasis upon CT re-examination.

Conclusions

Early detection of primary tracheal LELC allows for curative resection and may lead to a favorable prognosis. It presents with characteristic CT findings, and the utilization of PET-CT improves diagnosis and staging.

International Society of Urological Pathology (ISUP) Consensus Conference on Current Issues in Bladder Cancer. Working Group 2: Grading of Mixed Grade, Invasive Urothelial Carcinoma Including Histologic Subtypes and Divergent Differentiations, and Non-Urothelial Carcinomas

The 2022 International Society of Urological Pathology (ISUP) Consensus Conference on Urinary Bladder Cancer Working Group 2 was tasked to provide evidence-based proposals on the applications of grading in noninvasive urothelial carcinoma with mixed grades, invasive urothelial carcinoma including subtypes (variants) and divergent differentiations, and in pure non-urothelial carcinomas. Studies suggested that predominantly low-grade noninvasive papillary urothelial carcinoma with focal high-grade component has intermediate outcome between low- and high-grade tumors. However, no consensus was reached on how to define a focal high-grade component. By 2004 WHO grading, the vast majority of lamina propria-invasive (T1) urothelial carcinomas are high-grade, and the rare invasive low-grade tumors show only limited superficial invasion. While by 1973 WHO grading, the vast majority of T1 urothelial carcinomas are G2 and G3 and show significant differences in outcome based on tumor grade. No consensus was reached if T1 tumors should be graded either by the 2004 WHO system or by the 1973 WHO system. Because of the concern for underdiagnosis and underreporting with potential undertreatment, participants unanimously recommended that the presence of urothelial carcinoma subtypes and divergent differentiations should be reported. There was consensus that the extent of these subtypes and divergent differentiations should also be documented in biopsy, transurethral resection, and cystectomy specimens. Any distinct subtype and divergent differentiation should be diagnosed without a threshold cutoff, and each type should be enumerated in tumors with combined morphologies. The participants agreed that all subtypes and divergent differentiations should be considered high-grade according to the 2004 WHO grading system. However, participants strongly acknowledged that subtypes and divergent differentiations should not be considered as a homogenous group in terms of behavior. Thus, future studies should focus on individual subtypes and divergent differentiations rather than lumping these different entities into a single clinicopathological group. Likewise, clinical recommendations should pay attention to the potential heterogeneity of subtypes and divergent differentiations in terms of behavior and response to therapy. There was consensus that invasive pure squamous cell carcinoma and pure adenocarcinoma of the bladder should be graded according to the degree of differentiation. In conclusion, this summary of the International Society of Urological Pathology Working Group 2 proceedings addresses some of the issues on grading beyond its traditional application, including for papillary urothelial carcinomas with mixed grades and with invasive components. Reporting of subtypes and divergent differentiation is also addressed in detail, acknowledging their role in risk stratification. This report could serve as a guide for best practices and may advise future research and proposals on the prognostication of these tumors.

[Morphological variants of the invasive urothelial cell carcinoma.]

Urothelial cell carcinoma is the most common malignant tumor of the urinary tract, which develops in the renal pelvis, ureter, and bladder, and rarely it develops in the ureter. Histologically, urothelial cell carcinoma is categorized into non-invasive and invasive forms. Non-invasive urothelial cell carcinoma has papillary growth, it is usually well differentiated, and has a favorable outcome, while invasive urothelial cell carcinoma infiltratively spreads the organs of origin, it is typically poorly differentiated, and often associated with a poor prognosis. In the case of invasive urothelial cell carcinoma, the clinical course is primarily determined by the depth of invasion, but according to recent data, morphological variants of urothelial cell carcinoma respond differently to oncological treatments, and their biological behavior is also distinct. These subtypes and variants are significantly underdiagnosed in Hungary and internationally because the criteria for histological diagnosis are not clear for many subsets. The latest 2022 WHO classification of urinary tract tumors significantly clarified the definitions of various subtypes and variants. In this paper, utilizing the current classification, we review and explain these subtypes' morphological, immunohistochemical, differential diagnostic, prognostic, and predictive characteristics intending to make them appear as much as possible in everyday diagnostic practice. Also, the work aims to present the individual urothelial cell carcinoma subtypes and variants to the Hungarian community of pathologists, oncologists, and urologists, so that the previously high level of urological oncology care can become even more personalized. Orv Hetil. 2023; 164(40): 1567-1582.

Prognostic value of LI-RADS category on MRI in patients with primary hepatic lymphoepithelioma-like carcinoma

OBJECTIVES

To compare the clinical and MRI features of primary hepatic lymphoepithelioma-like carcinoma (LELC) categorized as LR-M or LR-4/5 using the Liver Imaging Reporting and Data System (LI-RADS) version 2018 and to determine the prognostic factors for recurrence-free survival (RFS).

METHODS

In this retrospective study, 37 patients with surgically confirmed LELC were included. Two independent observers evaluated preoperative MRI features according to the LI-RADS version 2018. Clinical and imaging features were compared between two groups. RFS and the associated factors were evaluated using Cox proportional hazards regression analysis, Kaplan-Meier analysis, and log-rank test.

RESULTS

In total, 37 patients (mean age, 58.5 ± 10.3 years) were evaluated. Sixteen (43.2%) LELCs were categorized as LR-M and twenty-one (56.8%) LELCs were categorized as LR-4/5. In the multivariate analysis, the LR-M category was an independent factor for RFS (HR 7.908, 95% CI 1.170-53.437; p = 0.033). RFS rates were significantly lower in patients with LR-M LELCs than in patients with LR-4/5 LELCs (5-year RFS rate, 43.8% vs.85.7%; p = 0.002).

CONCLUSION

The LI-RADS category was significantly associated with postsurgical prognosis of LELC, with tumor categorized as LR-M having a worse RFS than those categorized as LR-4/5.

KEY POINTS

• Lymphoepithelioma-like carcinoma patients categorized as LR-M have worse recurrence-free survival than those categorized as LR-4/5. • MRI-based LI-RADS categorization was an independent factor for postoperative prognosis of primary hepatic lymphoepithelioma-like carcinoma.

Prognostic impact of variant histologies in urothelial bladder cancer treated with radical cystectomy

OBJECTIVES

To evaluate variant histologies (VHs) for disease-specific survival (DSS) in patients with invasive urothelial bladder cancer (BCa) undergoing radical cystectomy (RC).

MATERIALS AND METHODS

We analysed a multi-institutional cohort of 1082 patients treated with upfront RC for cT1-4aN0M0 urothelial BCa at eight centres. Univariable and multivariable Cox' regression analyses were used to assess the effect of different VHs on DSS in overall cohort and three stage-based analyses. The stages were defined as 'organ-confined' (≤pT2N0), 'locally advanced' (pT3-4N0) and 'node-positive' (pTanyN1-3).

RESULTS

Overall, 784 patients (72.5%) had pure urothelial carcinoma (UC), while the remaining 298 (27.5%) harboured a VH. Squamous differentiation was the most common VH, observed in 166 patients (15.3%), followed by micropapillary (40 patients [3.7%]), sarcomatoid (29 patients [2.7%]), glandular (18 patients [1.7%]), lymphoepithelioma-like (14 patients [1.3%]), small-cell (13 patients [1.2%]), clear-cell (eight patients [0.7%]), nested (seven patients [0.6%]) and plasmacytoid VH (three patients [0.3%]). The median follow-up was 2.3 years. Overall, 534 (49.4%) disease-related deaths occurred. In uni- and multivariable analyses, plasmacytoid and small-cell VHs were associated with worse DSS in the overall cohort (both P = 0.04). In univariable analyses, sarcomatoid VH was significantly associated with worse DSS, while lymphoepithelioma-like VH had favourable DSS compared to pure UC. Clear-cell (P = 0.015) and small-cell (P = 0.011) VH were associated with worse DSS in the organ-confined and node-positive cohorts, respectively.

CONCLUSIONS

More than 25% of patients harboured a VH at time of RC. Compared to pure UC, clear-cell, plasmacytoid, small-cell and sarcomatoid VHs were associated with worse DSS, while lymphoepithelioma-like VH was characterized by a DSS benefit. Accurate pathological diagnosis of VHs may ensure tailored counselling to identify patients who require more intensive management.

Case Report: Primary lymphoepithelioma-like intrahepatic cholangiocarcinoma

BACKGROUND

Lymphoepithelioma-like intrahepatic cholangiocarcinoma (LEL-ICC) is a rare variant of intrahepatic cholangiocarcinoma. Epstein-Barr virus (EBV) infection was considered to play a pivotal role in the tumorigenesis of LEL-ICC. It is difficult to diagnosis of LEL-ICC due to the lack of specific features regarding the laboratory test results and imaging findings. At present, the diagnosis of LEL-ICC mainly depends on the histopathologic and immunohistochemical examinations. In addition, the prognosis of LEL-ICC was better than classical cholangiocarcinomas. To our knowledge, only few cases of LEL-ICC have been reported in the literature.

CASE PRESENTATION

We presented a case of a 32-year-old Chinese female with LEL-ICC. She had a 6-month history of upper abdominal pain. The magnetic resonance imaging (MRI) showed a 1.1× 1.3 cm lesion in the left lobe of liver, appearing low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. The patient underwent laparoscopic left lateral sectionectomy. The postoperative histopathologic and immunohistochemical examinations results allowed for the definitive diagnosis of LEL-ICC. The patient was free from tumor recurrence after a 28 months follow-up.

CONCLUSION

In this study, we reported a rare case of LEL-ICC associated with both HBV and EBV infection. EBV infection might play a pivotal role in the carcinogenesis of LEL-ICC, and surgical resection is still the most effective treatment at present. Further research on the etiology and treatment strategies of LEL-ICC is required.

Urinary Bladder Masses, Rare Subtypes, and Masslike Lesions: Radiologic-Pathologic Correlation

Urinary bladder masses are commonly encountered in clinical practice, with 95% arising from the epithelial layer and rarer tumors arising from the lamina propria, muscularis propria, serosa, and adventitia. The extent of neoplastic invasion into these bladder layers is assessed with multimodality imaging, and the MRI-based Vesical Imaging Reporting and Data System is increasingly used to aid tumor staging. Given the multiple layers and cell lineages, a diverse array of pathologic entities can arise from the urinary bladder, and distinguishing among benign, malignant, and nonneoplastic entities is not reliably feasible in most cases. Pathologic assessment remains the standard of care for classification of bladder masses. Although urothelial carcinoma accounts for most urinary bladder malignancies in the United States, several histopathologic entities exist, including squamous cell carcinoma, adenocarcinoma, melanoma, and neuroendocrine tumors. Furthermore, there are variant histopathologic subtypes of urothelial carcinoma (eg, the plasmacytoid variant), which are often aggressive. Atypical benign bladder masses are diverse and can have inflammatory or iatrogenic causes and mimic malignancy. ^© RSNA, 2022 Online supplemental material is available for this article.

Neoadjuvant chemotherapy for muscle-invasive bladder cancer: does variant histology matter?

PURPOSE

The most frequent histology of bladder tumors is urothelial carcinoma. Most are pure urothelial carcinomas (PUC) but up to one-third of the cases present variant histological (VH) features. The aim of this study was to evaluate the role of variant histology in neoadjuvant chemotherapy (NAC) response in patients with urothelial muscle-invasive bladder cancer.

METHODS

We retrospectively analyzed data from 77 patients with bladder cancer who performed neoadjuvant chemotherapy at two institutions.

RESULTS

Complete pathological response (ypT0) was higher in patients with PUC (38.5%), comparing with VH (12%). Logistic regression analysis demonstrated that variant histology is associated with an 89% lesser likelihood of tumor downstaging, with advanced clinical T stages and positive smoking history as independent predictors. The estimated mean cancer-specific survival was 68.91 months for PUC patients and 50.23 months for VH patients (log rank test, P = 0.024). Multivariate Cox regression analysis demonstrated that VH and clinical T stage were independent predictors of cancer-specific survival, indicating a worse outcome for patients with VH and advanced clinical T stages.

CONCLUSIONS

There are only a few retrospective studies evaluating the clinical impact of variant histology tumors, which are mainly managed as PUC. Our results demonstrate that VH is associated with a worse likelihood of tumor downstaging after NAC and a worse cancer-specific survival in bladder cancer patients. There is a need for further studies and genetic analysis to identify the patients most likely to achieve ypT0 status and downstaging after NAC.

Overview of histologic variants of urothelial carcinoma: current trends and narrative review on treatment outcomes

Background and Objective

The histologic variants of urothelial carcinoma (UC) are tumors arising from within the urothelium in which some component of the tumor morphology is other than urothelial. They are underdiagnosed, aggressive and have varying pathologic response rates to systemic chemotherapy. There are no consensus guidelines on the use of systemic chemotherapy in variant histology (VH) of UC. We performed a contemporary review on pathologic response rates to neoadjuvant systemic therapy and survival outcomes following radical cystectomy in order to provide a rationale for clinical practice recommendations on the management of UC with VH.

Methods

A PubMed literature search was conducted for all English articles from inception reporting either pathological response rates to neoadjuvant treatment or survival outcomes after radical cystectomy in non-metastatic VH of UC.

Key Content and Findings

Neoadjuvant chemotherapy (NAC) prior to radical cystectomy was shown to be a beneficial treatment strategy in UC with VH. The micropapillary, plasmacytoid, nested and sarcomatoid histologic variants were associated with worse survival outcomes compared to conventional UC and UC with squamous or glandular differentiation despite initial downstaging with chemotherapy. There is evidence of improved survival in patients with sarcomatoid differentiation receiving NAC compared to RC alone. The major prognostic factors that affect survival outcomes in VH of UC include histologic variant subtype, patient age, presence of lymphovascular invasion, hydronephrosis, nodal metastasis and advanced T stage at diagnosis. Recent studies demonstrate that VH of UC are heterogenous tumors and responsiveness to NAC may be a function of the molecular subtypes present.

Conclusions

Based on these findings, NAC to achieve pathologic downstaging prior to radical cystectomy is recommended for MIBC with VH. Biomarkers identified by molecular profiling with immunohistochemistry will need to be validated as predictors of response to NAC in future trials.

Demographics, clinical features, and prognosis of rare lymphoepithelioma-like carcinoma across different anatomic sites

Background

Lymphoepithelioma-like carcinoma (LELC) is an unusual histological malignancy type. Due to the rarity of this disease, we used the Surveillance, Epidemiology, and End Results (SEER) database to investigate comprehensively and systematically the prognosis factor of LELC.

Methods

We identified 2079 patients diagnosed with LELC during 1973–2015 from the SEER database. LELC was classified according to the tumor site. We analyzed the clinical characteristics and estimated the hazard ratio (HR) of overall mortality of LELC at each site.

Results

The nasopharynx was the most frequent site where LELC (58%) occurred. A large percentage of nasopharyngeal and pulmonary LELC patients were of Asian descent (44.5 and 32.56%, respectively). Furthermore, the majority of LELC patients were rather young when diagnosed. However, urinary bladder LELC and digestive system LELC (mean age: 69.03 and 68.05 years, respectively) were mainly to be found in older patients. Then according to Kaplan–Meier survival analysis, we found that patients with pulmonary LELC had worse survival. After adjusting for clinical tumor characteristics, pulmonary LELC patients were at increased risk of overall mortality compared with nasopharyngeal LELC either at the localized stage (HR 3.12, 95% confidence interval [CI], 1.55–6.26. P < 0.01) or at the regional stage (HR 1.72, 95% CI 1.03–2.88 P = 0.04).

Conclusions

In conclusion, we found that urinary bladder and digestive system LELCs mainly were diagnosed in old people and different from other LELCs. Pulmonary LELC patients might have a bad prognosis. The origination site may represent a predictive factor for determining survival in patients with LELC.

OUP accepted manuscript

Bladder lymphoepithelioma-like carcinoma is a rare entity. It represents a particular variant of urothelial carcinoma characterized by an important infiltrating power. Therapeutic management of this cancer is not codified. Surgery associated with chemotherapy seems to be the best therapeutic option. Few cases of this tumor have been reported in the literature. We report a case of bladder lymphoepithelioma-like carcinoma in a 52-year-old patient who presented with gross hematuria and discusses difficulties of diagnostic and treatment.

Bladder Cancer Sample Handling and Reporting: Pathologist's Point of View

The aim of this narrative review is to provide adequate information on handling and reporting of the bladder cancer samples to improve the closely collaboration between pathologists and urologists. The main (but not exclusive) research tool used was PubMed and 87 references were selected and quoted in the text. We have considered handling of biopsies, transurethral resection (TUR), and cystectomy specimens to summarize the different methods of sampling and the related issues. Moreover, we considered and discussed the main prognostic factors, such as histological tumor type, grade, and stage of bladder cancer, that should be described in the pathological report. In addition, critical issues encountered in the interpretation of histological samples were discussed.

Survival Analysis of Lymphoepithelioma-Like Carcinoma of the Urinary Bladder and the Effect of Surgical Treatment Modalities on Prognosis

Purpose: This study aimed to investigate the prognostic factors of patients with lymphoepithelioma-like carcinoma of the urinary bladder (LELCB) and explore the value of surgical treatment. Methods: Data of patients with LELCB were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. The multivariate analysis was performed using the stepwise Cox proportional hazards regression model and conditional inference tree method to identify significant prognosticators of overall survival (OS) from the parameters such as age, gender, lymph node involvement, tumor extent, radiation, chemotherapy, and surgery type. Literature review (LR) was performed, and eligible cases were used to validate prognostic classification using the Kaplan-Meier method with log-rank tests. Results: Sixty patients with a median age of 69.5 years were identified from the SEER database and 91 patients through LR. The Cox analysis identified age, gender, lymph node involvement, and surgical approach as independent prognosticators of OS. Based on the nomogram scores, patients were stratified into three prognostic groups: (I) patients younger than 70 years; (II) patients older than 70 years, who received bladder-sparing therapy (BST); and (III) patients older than 70 years undergoing radical cystectomy (RC). Patients in group II had the worst outcomes in terms of OS compared with patients in groups I and III (p < 0.001 and p = 0.03, respectively). A similar survival pattern was found in the LR cohort. Conclusion: The nomogram provided individualized prognostic quantification of OS in patients with LELCB. BST could yield favorable outcomes when treating LELCB, especially for younger patients, whereas older patients might derive more survival benefit from RC.

Lymphoepithelioma like carcinoma of the urinary bladder, treated with transurethral resection and intravesical Bacillus Calmette Guerin therapy only: A case report

Lymphoepithelioma-like urotehelial carcinoma which was first identified by Zukerberg, constitutes 0,4-1,3% of all urothelial carcinomas and has similar histomorphological features with nasopharyngeal lymphoepithelioma. We report a case of predominant lymphoepithelioma like bladder carcinoma in a 72 years old male patient. Transuretheral resection of the bladder and adjuvant intravesical Bacillus Calmette Guerin treatment was applied. The patient is currently at the 16th month after diagnosis and no recurrence or metastasis has been observed in cystoscopic and radiological examinations.

Lymphoepithelioma-like Intrahepatic Cholangiocarcinoma Is a Distinct Entity With Frequent pTERT/TP53 Mutations and Comprises 2 Subgroups Based on Epstein-Barr Virus Infection

The molecular characteristics of lymphoepithelioma-like intrahepatic cholangiocarcinoma (LELCC) remain elusive. We examined 27 LELCC cases through next-generation sequencing using a panel of genes commonly mutated in primary liver cancers. Alterations in BAP1, ARID1A, ARID2, and PBRM1 were detected through immunohistochemistry. Fluorescence in situ hybridization was performed to analyze FGFR2 fusions and CCND1 amplification. LELCC is histologically classified as predominantly undifferentiated or glandular. Epstein-Barr virus-encoded small RNA (EBER) expression was found in 16 LELCCs. Approximately 50% of LELCCs expressed programmed death-ligand 1 strongly. Notably, recurrent pTERT and TP53 mutations were detected in 9 (38%) and 8 (33%) tumors, respectively. Only 2 LELCCs exhibited loss of expression for PBRM1. Alterations in genes typically involved in intrahepatic cholangiocarcinoma, including IDH1, IDH2, ARID1A, ARID2, and BAP1, and FGFR2 fusions, were not identified. The 2-step clustering analysis showed 2 distinct subgroups in LELCC, which were separated by EBER expression. A meta-analysis of all reported cases (n=85) has shown that EBER+ LELCC is strongly associated with the female sex, younger age, and exhibited predominantly glandular differentiation (P=0.001, 0.012, and <0.001, respectively). Patients with EBER- LELCC were more likely to have viral hepatitis and cirrhosis (P=0.003 and 0.005, respectively). Genetic analysis demonstrated that EBER- LELCC was significantly associated with pTERT and TP53 mutations (P=0.033 and 0.008, respectively). In conclusion, LELCC is genetically distinct from intrahepatic cholangiocarcinoma. EBER- LELCC may exhibit a different pathogenesis from EBER+ LELCC. High programmed death-ligand 1 expression in LELCC has implications for potential immunotherapeutic strategies.

Histologic Variants of Urothelial Carcinoma: Morphology, Molecular Features and Clinical Implications

Bladder cancer is a heterogeneous disease including conventional urothelial carcinoma (UC) and its histologic variants, and non-urothelial carcinoma, including squamous and glandular neoplasms. Urothelial carcinoma accounts for the majority of bladder cancer cases, but morphologic variants are common and include nested, microcystic, micropapillary, lymphoepithelioma-like, plasmacytoid, sarcomatoid, giant cell, undifferentiated, clear cell and lipoid. Certain variants of UC tend to be associated with a poor prognosis and have diagnostic and potential treatment implications that make the identification of variant histology crucial to clinical decision making. While there is still uncertainty regarding the prognostic implications of many of these variants, identifying and reporting variant histology is important to develop our understanding of their biology. Unique molecular features accompany many of these morphologic variants and to better understand these tumors, we review the molecular and clinical implications of histologic variants of bladder cancer. Major efforts are underway to include variant histology and divergent differentiation of UC in clinical trials to develop evidence based approaches to treatment. The purpose of this article is to review the current literature on variant histology of urothelial cancer and to highlight molecular findings and the clinical relevance of these tumors.

Simultaneous upper and lower urinary tract invasive Lymphoepithelioma-like carcinoma with programmed death-ligand 1 full expression on combined positive score

Lymphoepithelioma-like carcinoma, named after nasopharyngeal lymphoepithelioma and rarely seen at genitourinary malignancy, accounts for 1%–2% along the upper and lower urinary tract. For its rarity, no published guideline can be adhered to. Roles of surgery and chemotherapy are solid, and rich Programmed Death-Ligand 1 characteristics may furthermore light on the possible immunotherapy. This female case had it at both upper and lower urinary tract simultaneously. No involved regional lymph nodes and no distant metastasis were investigated. No adjuvant chemotherapy was given after robotics-assisted left nephroureterectomy and bladder cuff excision with partial cystectomy, and no recurrence was observed.

Primary pulmonary lymphoepithelioma-like carcinoma: a rare type of lung cancer with a favorable outcome in comparison to squamous carcinoma

Background

Primary pulmonary lymphoepithelioma-like carcinoma (LELC) is a rare tumor and often misdiagnosed as squamous carcinoma. In the current study, clinical characteristics and outcome of primary pulmonary LELC were systematically compared with pulmonary squamous carcinoma.

Methods

Forty-two cases of primary pulmonary LELC and 134 squamous carcinomas were enrolled retrospectively. Characteristic and prognosis difference between the two groups was compared, and the independent prognostic factor for pulmonary LELC was identified as well.

Results

In comparison to squamous carcinoma, pulmonary LELC was more common in women with a younger median age and less smokers. LELC seemed to be smaller in diameter on computed tomography (CT) scans than squamous carcinoma, with scarce spiculation and vascular convergence signs. Epstein-Bar virus-encoded RNA (EBER) by in-situ hybridization was detected in 33 LELC cases, among whom 27 ones were positive in serum EBV-DNA examination. LELC patients presented a much longer median progression-free survival (PFS) than squamous carcinoma. Positive serum EBV-DNA, distant lymph node invasion, advanced clinical stage and receiving radiotherapy were correlated with the shorter PFS in LELC patients. However, only positive serum EBV-DNA was the independent PFS predictor.

Conclusion

Pulmonary LELC looks like distinct from squamous carcinoma. Middle-aged women and nonsmokers are comparatively predominated. CT features of pulmonary LELC are relatively less-malignant. Correspondently, the progression of pulmonary LELC is seemingly favorable than squamous carcinoma and the positive serum EBV-DNA appears to be the predictor of PFS.

Lymphoepithelioma-like intrahepatic cholangiocarcinoma with Epstein-Barr virus infection: report of a rare case

Lymphoepithelioma-like intrahepatic cholangiocarcinoma (LEL-ICC) is an uncommon lesion. Less than 100 cases of hepatic LELC, including IEL-HCC (hepatocellular carcinoma) and IEL-ICC, have been described, and the understanding of the LELC is very limited. We report the case of a 75-year-old woman with LEL-ICC. She complained of finding a lesion located in the left lateral liver during her last check-up 2 years ago. The contrast-enhanced abdominal computed tomography (CT) scan revealed a low-density mass located in the left lateral liver with an estimated magnitude of 20×16 mm. The magnetic resonance imaging (MRI) demonstrated two T2 high-signal intensity foci in the left lateral liver, with similar size and signal manifestation in the arterial and portal venous phases. The patient underwent laparoscopic left lateral hepatectomy. The postoperative pathological and immunohistochemical examination findings allowed for the definitive diagnosis. A literature review indicated that a geriatric Asian female with a single lesion located in the liver should consider the possibility of LEL-ICC. An Epstein-Barr virus (EBV) infection might play a crucial role in the tumorigenesis of LEL-ICC, and surgical resection was the first choice for treating LEL-ICC.

Lymphoepithelioma-Like Carcinoma of the Bladder: A Case Report of a Rare and Particular Variant of Urothelial Carcinoma

Lymphoepithelioma-like carcinoma of the bladder (LELCB) is a rare variant of urothelial carcinoma first described by Zukerberg in 1991 and confirmed as a variant of urothelial carcinoma by the WHO classification of tumors of the urinary system. LELCB is characterized by a marked infiltration of lymphocytes in the area involved by the tumor which may coexist with the conventional urothelial carcinoma. LELCB are classified according to the percentage of lymphoepithelioma component within the tumor with the prognosis depending on the percentage. We report a new case of pure LELCB occurring in 63-year-old woman presenting with hematuria. Ultrasonography and cystoscopy revealed a large tumor on the left lateral wall of the bladder. Transurethral resection of the bladder tumor (TURBT) was performed. Pathological and immunohistochemical analysis revealed a high-grade muscle-invasive LELCB (G3pT2). The patient underwent an adjuvant systemic chemotherapy with no recurrence after a ten-month follow-up. To our knowledge, this is the second Moroccan case of LELCB reported in the English literature. Although its rare occurrence prognosis and ideal therapeutic management of LELCB have not been clearly established yet, literature findings encourage the adoption of a conservative approach in treatment of LELCB.

EBV-associated lymphoepithelioma-like thyroid carcinoma with favorable outcome: case report with cytopathologic and histopathologic study

Background

Lymphoepithelioma-like carcinoma (LELC) is a rare entity among thyroid tumors. Based on the limited number of case reports that exist, the association of Epstein–Barr virus (EBV) with primary thyroid LELCs seems inconsistent.

Case presentation

We present a confusing cytological case of lymphoepithelioma-like thyroid carcinoma with expression of EBV. The patient presented with a central neck mass and bilateral lymphadenopathy. Fine-needle aspiration cytology revealed three-dimensional and syncytial fragments of epithelioid cells accompanied by small lymphocytes. The surgical specimen of resected thyroid tumor disclosed typical histopathological features of LELC. Metastatic papillary carcinoma was also discovered in the metastatic lymph nodes. In situ hybridization for EBV-encoded RNA (EBER-ISH) was positive in the tumor cells. Negative immunoreactivity for TTF-1, Pax-8, and CD5 was observed. The patient is currently undergoing regular follow-up and is 1 year and 10 months postresection with no evidence of recurrence.

Conclusions

Long-term survival is discussed in relation to this variant of thyroid carcinoma, which might differ in behavior from anaplastic carcinoma. Further investigation is required to elucidate the clinical significance of EBV expression and progression of this unique variant of thyroid carcinoma.