Plasmacytoid Variant Urothelial Carcinoma of the Bladder: A Systematic Review and Meta-Analysis of Clinicopathological Features and Survival Outcomes

Neoadjuvant Chemotherapy Prior to Radical Cystectomy for Muscle-Invasive Bladder Cancer With Variant Histology: A Systematic Review and Meta-Analysis of Survival Outcomes and Pathological Features

PURPOSE

To conduct systematic review and meta-analysis to evaluate effects of neoadjuvant chemotherapy (NAC) on survival and histopathological outcomes of variant histology (VH) of urothelial carcinoma (UC) of bladder.

METHODS

This systematic review was registered in PROSPERO (CRD42023389115). Literature search was conducted in PubMed/Medline, Embase, and Cochrane Library for studies published up to January 2023. Population, intervention, comparator, outcome, and study design were as follows: bladder cancer patients with VH (population), neoadjuvant chemotherapy (intervention), radical cystectomy only (comparators), oncological survival and pathologic response (outcomes), and retrospective or prospective (study design).

RESULTS

Finally, a total of 17 studies were included in the present study (quantitative analysis, n = 17; qualitative analysis, n = 12). Pooled HR was 0.49 (95% CI: 0.31-0.76; P = .002) for OS. Pooled HR was 0.61 (95% CI: 0.38-0.98; P = .04) for CSS. Pooled HR was 0.44 (95% CI: 0.21-0.93; P = .03) in PFS. Pooled OR was 6.61 (95% CI: 4.50-9.73; P < .00001) in complete pathologic response. Pooled OR was 9.59 (95% CI: 3.56-25.85; P < .00001) in any pathologic response. Evidence quality assessments for each 5 comparisons using the GRADE approach were that Certainty was moderate in 1, low in 1, and very low in 3.

CONCLUSIONS

Administration of NAC before surgery in bladder cancer patients with VH might confer better survival outcomes and higher pathologic down staging rate than no administration of NAC before surgery.

One Size Fits Some: Approaching Rare Malignancies of the Urinary Tract

OPINION STATEMENT

Urothelial carcinoma is the predominant cancer of the urinary tract but when divergent and subtype histology (non-urothelial) are identified at time of pathologic diagnosis, therapeutic and diagnostic challenges transpire. To this end, pathologic review to confirm any non-urothelial histology is key since these subtypes can often be overlooked. Few prospective trials are dedicated to understanding these non-urothelial histologic types; however, current, and past trials did allow patients with these non-urothelial histologic types to enroll, and inferences can be made about treatment efficacy and survival. Existing treatment regimens for non-urothelial bladder cancers are akin to standard urothelial cancer regimens using surgical approaches for localized disease and platinum-based chemotherapy for advanced disease. The reported clinical trials, that will be discussed, center on non-urothelial histologic types. These studies, albeit limited, provide critical insight into tumor biology and response to standard platinum-based chemotherapy, immune checkpoint inhibitors, and antibody drug conjugates. The inclusion of non-urothelial histologic types will be essential for clinical trials in development to provide further therapeutic advances and provide essential efficacy data.

The perioperative and long-term outcomes of patients with variant histology bladder cancer undergoing radical cystectomy: A propensity score-matched analysis with pure urothelial carcinoma

OBJECTIVES

To assess the perioperative and long-term outcomes after open radical cystectomy in patients with histological variants versus pure urothelial carcinoma.

METHODS

Patients with a variant histology carcinoma of the urinary bladder were matched through a propensity score analysis with those with pure urothelial carcinoma on a 1:3 ratio. The two groups were compared in terms of perioperative and long-term morbidity and mortality.

RESULTS

Overall, 148 individuals were included in the present retrospective study (37 with variant histology and 111 with pure urothelial carcinoma). A total of 107 (72.3%) individuals presented at least one perioperative complication based on the Clavien-Dindo classification. This proportion was similar between patients with urothelial versus variant histology carcinoma (P = .22). In the long term, the number of patients with clinically significant incisional hernia requiring surgery [14 (12.7%) vs 3 (8.3%), P = .68], uretero-intestinal/uretero-cutaneous strictures or any other complication related to the applied urinary diversion [15 (13.6%) vs 7 (19.4%), P = .56], as well as the number of patients presenting with septicemia [17 (15.5%) vs 10 (27.8%), P = .16] or with urinary tract obstruction [12 (10.9%) vs 4 (11.1%), P > .99] at follow-up did not differ between urothelial versus variant histology carcinoma. The survival analysis with Kaplan-Meier curves and the univariate Cox regression model suggested that the risk of death from any cause was increased in patients with variant compared to pure urothelial histology (log-rank test = 0.045, hazard ratio: 1.7, 95% confidence interval: 1.01-2.87, P = .047).

CONCLUSIONS

Perioperative morbidity and mortality are comparable in patients with variant histology versus pure urothelial carcinoma.

Impact of surgical margin and extent of lymphadenectomy on oncologic outcomes in plasmacytoid urothelial carcinoma

OBJECTIVE

Guideline recommendations disagree on template boundaries for pelvic lymph node dissection (PLND) in conventional urothelial carcinoma. Less is known about PLND in variant histology. We aimed to analyze the role of LND in plasmacytoid urothelial carcinoma (PUC).

METHODS

A retrospective review of patients with cTanyNanyM0 PUC who underwent radical cystectomy (RC) with PLND was performed from 2012 to 2022. Lymph node count (LNC) was a surrogate for extent of lymph node dissection and dichotomized based on maximally selected rank statistics. Multivariable cox hazard regression analysis (MVA) for overall survival (OS) corrected for age, perioperative chemotherapy, soft tissue margin status, and stage ≥pT3 and/or pN+ was performed. Disease free survival (DFS) and OS were estimated using Kaplan-Meier (KM) analysis.

RESULTS

Sixty-seven patients with median age of 71, who were 79.1% male were included. Neoadjuvant and adjuvant chemotherapy were administered in 61.2% and 19.4% of patients, respectively. At RC, 70.1% were ≥pT3. Median LNC was 22 (IQR 14-27) with 43.3% of patients being pN+. Calculated optimal-LNC cut point for DFS and OS was 19. Grouping by optimal (≥20) vs. suboptimal-LNC (<20), no significant clinicodemographic differences were found. Optimal-LNC provided improved DFS (P = 0.05) and OS (P = 0.02). Optimal-LNC (HR 0.47, 0.24-0.93 CI 95%, P = 0.03) and negative soft tissue margin (HR 0.38, 0.19-0.76 CI 95%, P = 0.01) was associated with improved OS on MVA. Receipt of perioperative chemotherapy did not improve OS (P = 0.46).

CONCLUSION

In PUC, complete surgical extirpation achieving negative soft tissue margins and removing ≥20 lymph should be prioritized if operative intervention is pursued.

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.

A case of Avelumab response to multiple bone and lymph node metastases of plasmacytoid variant bladder cancer

A 74-year-old man was diagnosed with bladder cancer and referred to our department. For definitive diagnosis, transurethral resection of the bladder tumor(TURBT) was performed. The pathological result showed plasmacytoid variant of urothelial carcinoma. Subsequently, robot-assisted radical cystectomy, lymph node dissection and ileal conduit was performed, but multiple bone metastases and periaortic lymph node metastases newly appeared 30 days later. Gemcitabine and cisplatin (GC) was started, and after 4 courses, the patient became Partial Response (PR), and was switched to Avelumab as maintenance therapy. After about 1 year of maintenance therapy, the patient is still in PR.

Plasmacytoid Urothelial Carcinoma of the Bladder That Manifests Disseminated Carcinomatosis of the Bone Marrow: A Case Report of Extremely Rapid Progression

Plasmacytoid urothelial carcinoma (PUC) of the bladder is a rare variant of invasive urothelial carcinoma (UC) with aggressive behavior. Despite its prognosis being poorer than that of conventional UC, a median overall survival of approximately 2 years is ensured when it is treated with radical cystectomy (RC), and few patients die within a few months of RC. In this paper, we report the case of a patient with PUC who developed widespread bone metastasis only 6 weeks after RC, which resulted in death within 2 months postoperatively.

A methodologic survey on use of the GRADE approach in evidence syntheses published in high-impact factor urology and nephrology journals

Background

To identify and describe the use of the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach for rating the certainty of systematic reviews (SRs) evidence published in urology and nephrology journals.

Methods

SRs that were published in the top ten "urology and nephrology" journals with the highest impact factor according to the 2020 Journal Citation Reports (covering 2016–2020) were systematically searched and evaluated using the GRADE approach.

Results

A total of 445 SRs were researched. Sixty SRs of randomized control trials (RCTs) and/or non-randomized studies (NRSs) were evaluated using the GRADE approach. Forty-nine SRs (11%) rated the outcome-specific certainty of evidence (n = 29 in 2019–2020). We identified 811 certainty of evidence outcome ratings (n = 544 RCT ratings) as follows: very low (33.0%); low (32.1%); moderate (24.5%); and high (10.4%). Very low and high certainty of evidence ratings accounted for 55.0% and 0.4% of ratings in SRs of NRSs compared to 23.0% and 15.3% in SRs of RCTs. The certainty of evidence for RCTs and NRSs was downgraded most often for risk of bias and imprecision.

Conclusions

We recommend increased emphasis on acceptance of the GRADE approach, as well as optimal use of the GRADE approach, in the synthesis of urinary tract evidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01701-x.

Multiparametric magnetic resonance imaging of plasmacytoid urothelial carcinoma with histopathological correlation: A case report

Plasmacytoid urothelial carcinomas of the bladder are rare, aggressive variants with a poor prognosis. Few reports have described the correlation of histopathological features with multiparametric magnetic resonance imaging findings in the local staging of plasmacytoid urothelial carcinoma. An 82-year-old woman with hematuria was referred to our hospital. Magnetic resonance imaging showed diffuse bladder wall thickening, with different signal intensities in the 2 layers—inner and outer. This case suggests that the presence of diffuse bladder wall thickening and varying signal intensities in the 2 layers could aid in the local staging of plasmacytoid urothelial carcinoma. A thickened bladder wall with restricted diffusion suggests tumor invasion, indicating that the tumor can invade the organ in contact with the thickened bladder wall.

Pleural fluid metastasis of plasmacytoid urothelial carcinoma in comparison to micropapillary and conventional high-grade urothelial carcinoma: Cytologic and immuonohistochemical findings

Plasmacytoid urothelial carcinoma (PUC) is a rare but clinically aggressive variant of high-grade urothelial carcinoma (HGUC). Cytological features include single plasmacytoid neoplastic cells with N:C ratio around 0.5, eccentric nuclei, nuclear hyperchromasia, irregular nuclear membrane, and vacuolated cytoplasm. Micropapillary urothelial carcinoma (MPUC) is another clinically aggressive variant of HGUC that shares some overlapping features of PUC. The diagnosis of these two aggressive variants in pleural effusions can be challenging due to features mimicking adenocarcinoma, unusual immunochemistry profile, and confusion with differential diagnoses, especially when pertinent clinical information is unavailable. We present report on one case each of pleural fluid metastasis of PUC and MPUC respectively, and compare the findings with that of a metastatic conventional HGUC originally thought to be metastatic adenocarcinoma. The diagnosis of PUC was confirmed with immunohistochemical studies showing expression for cytokeratin, GATA-3, uroplakin II, and CD138, diminished or loss of E-cadherin membranous expression, negative expression for p63, p53, Epicam-BerEP4, Epicam-MOC31, and p120. The diagnosis of MPUC was confirmed with immunostain profile similar to that of PUC except positive stain for E-cadherin, p120, and p53. The diagnosis of HGUC was confirmed with immunohistochemical studies showing expression for cytokeratin, GATA-3, uroplakin II, p63, Epicam-BerEP4 (focal weak), and Epicam-MOC31. Our cases of metastatic urothelial carcinoma showed features mimicking adenocarcinoma and others, especially the MPUC and HGUC were diagnosed without prior tissue diagnosis of urothelial carcinoma. This report emphasizes the cytohistological and immunohistochemical details of urothelial carcinoma involving effusion fluid and discusses potential pitfalls in diagnosis.

Clinically undetected plasmacytoid urothelial carcinoma of the urinary bladder with non-mass-forming metastases in multiple organs: an autopsy case

This case report outlines a clinically undetected urinary bladder plasmacytoid urothelial carcinoma (PUC) with multiple metastases detected at autopsy. An 89-year-old man presented with edema in the lower limbs. Pleural fluid cytology revealed discohesive carcinomatous cells, although imaging studies failed to identify the primary site of tumor. The patient died of respiratory failure. Autopsy disclosed a prostate tumor and diffusely thickened urinary bladder and rectum without distinct tumorous lesions. Histologically, the tumor consisted of acinar-type prostate adenocarcinoma with no signs of metastasis. Additionally, small, plasmacytoid tumor cells were observed in the urinary bladder/rectum as isolated or small clustering fashions. These metastasized to the lungs, intestine, generalized lymph nodes in a non-mass-forming manner. Combined with immunohistochemical studies, these tumor cells were diagnosed PUC derived from the urinary bladder. Both clinicians and pathologists should recognize PUC as an aggressive histological variant, which can represent a rapid systemic progression without mass-forming lesions.

Plasmacytoid urothelial carcinoma of the bladder: MRI features and their association with survival

OBJECTIVES

Plasmacytoid urothelial carcinomas (PUC) of the bladder are rare variants known for diffuse and infiltrative spread, however their magnetic resonance imaging (MRI) features are not well established. We aimed to evaluate MRI features of PUC of the bladder and their association with survival.

METHODS AND MATERIALS

This retrospective single-center study included 41 patients with pathologically-proven bladder PUC of the bladder that underwent pre-treatment MRI between January 2000 and March 2020. Two radiologists reviewed MRIs independently followed by consensus with a third radiologist. On MRI, tumor extent, size, Vesical Imaging-Reporting and Data System (VI-RADS) scores (≥4, muscle-invasive; 5, extravesical extension [EVE]), pelvic peritoneal spread (PPS), hydronephrosis, pelvic adenopathy and clinicopathological factors of age, gender, pathological stage, and treatment type were extracted. Kaplan-Meier curves and Cox proportional-hazards models were used to evaluate association with survival.

RESULTS

Thirty-two men and 9 women (median age 70 years, IQR 64-76) were included. Most were muscle-invasive (n = 30 [73.2%]). On MRI, most tumors were diffuse (n = 28 [68.3%]), >5 cm (n = 30 [73.2%]), VI-RADS 4 to 5 (n = 36 [87.8%]) with features of EVE and (n = 31 [75.6%]) and PPS (n = 25 [61.0%]). Variables associated with survival were: Larger tumors (>5 cm; hazard ratio [HR] = 5.0; 95% confidence interval [CI] 1.6-15.5; P < 0.01), diffuse extent (HR = 4.0; 95% CI 1.4-11.2; P = 0.01), EVE (HR = 4.5; 95% CI 1.5-13.6; P < 0.01), PPS (HR = 3.0; 95% CI 1.2-7.4; P = 0.01), hydronephrosis (HR = 13.7; 95% CI 3.1-60.9; P < 0.01), pathologic stage (≥pT3 vs. pT1; HR = 5.6; 95% CI 1.3-22.0; P = 0.02), and margin positivity (HR = 4.4 [95% CI 1.2-16.4], P = 0.03).

CONCLUSION

PUCs of the bladder are commonly large, diffuse VI-RADS score 4 to 5 tumors with MRI features of EVE and PPS. These features and pathological stage were associated with survival.

Plasmacytoid variant urothelial carcinoma of the bladder: effect of radical cystectomy and chemotherapy in non-metastatic and metastatic patients

PURPOSE

Data about optimal management of plasmacytoid (PCV) bladder cancer patients are extremely scarce and limited by sample size. We focused on PCV bladder cancer patients to explore the effect of radical cystectomy (RC) and chemotherapy in non-metastatic (T _2-4N_0-3M₀), as well as in metastatic (T_anyN_anyM₁) subgroups.

METHODS

Using the Surveillance, Epidemiology and End Results database (2000-2016), we identified 332 PCV patients with muscle-invasive disease or higher (≥ T₂N₀M₀). Kaplan-Meier plots and Cox regression models addressed cancer-specific mortality (CSM).

RESULTS

In 332 PCV patients, median age was 68 years (Interquartile range [IQR]:58-76). Of those, 252 were non-metastatic patients (76%) vs 80 were metastatic patients (24%), at presentation. Of non-metastatic patients, 142 (56%) underwent RC and 131 (52%) underwent chemotherapy. Chemotherapy did not improve CSM in non-metastatic PCV. Conversely, RC was associated with lower CSM (hazard ratio [HR]: 0.51, p = 0.002). Median CSM-free survival was 48 vs 38 months for RC treated vs RC not treated. Of metastatic patients, 22 (28%) underwent RC and 42 (52%) underwent chemotherapy. Both chemotherapy and RC improved CSM in metastatic PCV. Median CSM-free survival was 12 vs 7 months for RC treated vs RC not treated (HR: 0.27, p < 0.001). Median CSM-free survival was 11 vs 4 months for chemotherapy exposed vs chemotherapy naïve (HR: 0.32, p = 0.002).

CONCLUSIONS

Although RC resulted in lower CSM, chemotherapy failed to show that effect in non-metastatic PCV patients. Conversely, both chemotherapy and RC resulted in statistically significantly lower CSM in metastatic PCV patients.

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.

Common Diagnostic Challenges and Pitfalls in Genitourinary Organs, With Emphasis on Immunohistochemical and Molecular Updates

CONTEXT.—

Lesions in the genitourinary (GU) organs, both benign and malignant, can demonstrate overlapping morphology, and practicing surgical pathologists should be aware of these potential pitfalls and consider a broad differential diagnosis for each specific type of lesion involving the GU organs. The following summary of the contents presented at the 6th Annual Chinese American Pathologists Association (CAPA) Diagnostic Course (October 10-11, 2020), supplemented with relevant literature review, exemplifies the common diagnostic challenges and pitfalls for mass lesions of the GU system of adults, including adrenal gland, with emphasis on immunohistochemical and molecular updates when relevant.

OBJECTIVE.—

To describe the common mass lesions in the GU system of adults, including adrenal gland, with emphasis on the diagnostic challenges and pitfalls that may arise in the pathologic assessment, and to highlight immunohistochemical workups and emerging molecular findings when relevant.

DATA SOURCES.—

The contents presented at the course and literature search comprise our data sources.

CONCLUSIONS.—

The diagnostic challenges and pitfalls that arise in the pathologic assessment of the mass lesions in the GU system of adults, including adrenal gland, are common. We summarize the contents presented at the course, supplemented with relevant literature review, and hope to provide a diagnostic framework to evaluate these lesions in routine clinical practice.

Outcomes of poorly differentiated and plasmacytoid variant bladder urothelial carcinoma

Objectives

The aim of this study is to assess the course and management of poorly differentiated bladder urothelial carcinoma (UC), including plasmacytoid UC (PUC), in our local area. Although bladder cancer is relatively common, PUC is a rare and aggressive subtype with a poor prognosis that is still poorly understood.

Materials and Methods

A retrospective assessment of all poorly differentiated high‐grade UC over the last 15 years (2005–2020) in the Hunter New England area was completed. In total, 37 patients were included, and PUC variant was compared with the remaining poorly differentiated UC.

Results

Of the included cases, eight were PUC, nine squamous variant, two neuroendocrine, and one sarcomatoid. Overall, 23 cases proceeded to cystectomy, 15 had chemotherapy (six neoadjuvant), and 11 had radiation therapy. In the PUC subgroup, three had metastatic disease at diagnosis (37.5%). Of the three PUC patients who underwent cystectomy, all were upstaged. Two PUC cases had adjuvant chemotherapy, and one case had radiation. Within the follow‐up period, the PUC group had a cause‐specific mortality of 50% with a mean survival in these patients of 202 days, compared with 37.9% cause‐specific mortality with survival of 671.55 days (p = 0.23) in all other undifferentiated UC cases; 5‐year cause‐specific mortality with Kaplan–Meier analysis was estimated at 26% compared with 59%, respectively (p = 0.058).

Conclusion

Poorly differentiated UC is demonstrated to have a poor prognosis with a high mortality rate, particularly when PUC is present. Given the rarity of these variants, further studies are necessary to explore the impact of current treatment options.

Plasmacytoid urothelial carcinoma (UC) are luminal tumors with similar CD8+ Tcell density and PD-L1 protein expression on immune cells as compared to conventional UC

BACKGROUND

Plasmacytoid urothelial carcinoma (UC) is a rare pathological variant of UC with low chemotherapeutic sensitivity and dismal outcomes. The molecular and immune profiles of such tumors remain poorly investigated.

METHODS

Herein, we investigated the phenotypical features of a cohort of plasmacytoid UC (n=32) by comparison to a control group of conventional high-grade UC with matched clinicopathological characteristics (n=30). Histopathological analysis included the following antibodies: p63, GATA3, CK5/6, CK20 and HER2. In addition, the density of intra-tumor CD8⁺ lymphocytes, and PD-L1 expression in tumor (TC) and immune cells (IC) were evaluated.

RESULTS

Plasmacytoid UC expressed GATA3 (97% vs 86% P=0.18), CK20 (59% vs 36% P=0.08) markers and showed a significantly higher rate of HER2 overexpression (2+ and 3+ score: 25% vs 0%, P<0.01) compared to controls. A significantly lower expression of CK5/6 (22% vs 56%, P<0.05) and p63 (41% vs 80%, P<0.05) was observed in plasmacytoid UC compared to controls. The density of tumor-infiltrating CD8+ cells was similar between plasmacytoid and conventional UC (P=0.9). PD-L1 expression on IC was similar compared to conventional UC (P=0.3).

CONCLUSIONS

Together, our study demonstrated that plasmacytoid UC belong to the luminal subtype and display a rather inflamed microenvironment similar to conventional UC. These data support the inclusion of plasmacytoid variant of UC in clinical trials evaluating immune checkpoint inhibitors monotherapy or combination immunotherapeutic strategies.

Accuracy of Transurethral Resection of the Bladder in Detecting Variant Histology of Bladder Cancer Compared with Radical Cystectomy

BACKGROUND

Correct identification of variant histologies (VHs) of bladder cancer (BCa) at transurethral resection of the bladder (TURB) could drive the subsequent treatment.

OBJECTIVE

To evaluate the concordance in detecting VHs between TURB and radical cystectomy (RC) specimens in BCa patients.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analyzed 1881 BCa patients who underwent TURB and subsequent RC at seven tertiary care centers between 1980 and 2018. VHs were classified as sarcomatoid, lymphoepithelioma-like, neuroendocrine, squamous, micropapillary, glandular, adenocarcinoma, nested, and other variants.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Concordance between TURB and RC was defined as the ability to achieve histological subtypes at TURB confirmed at RC specimen, and was expressed according to Cohen's kappa coefficient.

RESULTS AND LIMITATIONS

Of the patients, 14.6% and 21% were diagnosed with VH at TURB and RC specimens, respectively. The most common VHs at TURB were squamous, neuroendocrine, and micropapillary carcinoma (5.2%, 1.5%, and 1.5%, respectively). At RC, the most frequent VHs were squamous, micropapillary, and sarcomatoid carcinoma (7.2%, 3.0%, and 2.7%, respectively). The overall concordance in detecting VH was defined as slight concordance (coefficient: 0.18). Moderate concordance was found for neuroendocrine, adenocarcinoma, and squamous carcinoma (coefficient: 0.49, 0.47, and 0.41, respectively). Micropapillary, glandular, and other variants showed slight concordance (coefficient: 0.05, 0.17, and 0.12, respectively), while nested and sarcomatoid carcinoma showed fair concordance (coefficient: 0.32 and 0.26, respectively). Results may be limited by the absence of centralized pathological analysis.

CONCLUSIONS

A non-negligible percentage of patients were diagnosed with VH at both TURB and RC. TURB showed relatively low accuracy, ranging from poor to moderate, in detecting VHs. Our study underlines the need of additional diagnostic tools in order to identify VHs properly at precystectomy time and to improve patient survival outcomes.

PATIENT SUMMARY

In this report, we underlined the low accuracy of transurethral resection of the bladder in detecting variant histologies and the need for additional diagnostic tools.

Unusual Faces of Bladder Cancer

Simple Summary

The spectrum of architectural and cytological findings in UC is wide, although transitional cell carcinoma, either papillary or flat, low- or high-grade, constitutes the majority of cases in routine practice. Some of these changes are just mere morphological variations, but others must be recognized since they have importance for the patient. The goal of this review is to compile this histological variability giving to the general pathologist a general idea of this morphological spectrum in a few pages. The review also updates the literature focusing specifically on the morphological and immunohistochemical clues useful for the diagnosis and some selected molecular studies with prognostic and/or diagnostic implications.

Abstract

The overwhelming majority of bladder cancers are transitional cell carcinomas. Albeit mostly monotonous, carcinomas in the bladder may occasionally display a broad spectrum of histological features that should be recognized by pathologists because some of them represent a diagnostic problem and/or lead prognostic implications. Sometimes these features are focal in the context of conventional transitional cell carcinomas, but some others are generalized across the tumor making its recognition a challenge. For practical purposes, the review distributes the morphologic spectrum of changes in architecture and cytology. Thus, nested and large nested, micropapillary, myxoid stroma, small tubules and adenoma nephrogenic-like, microcystic, verrucous, and diffuse lymphoepithelioma-like, on one hand, and plasmacytoid, signet ring, basaloid-squamous, yolk-sac, trophoblastic, rhabdoid, lipid/lipoblastic, giant, clear, eosinophilic (oncocytoid), and sarcomatoid, on the other, are revisited. Key histological and immunohistochemical features useful in the differential diagnosis are mentioned. In selected cases, molecular data associated with the diagnosis, prognosis, and/or treatment are also included.