Prognostic impact of variant histology in bladder cancer: Would early and aggressive treatment shift the paradigm?

INTRODUCTION

Bladder cancer (BC) is an increasingly frequent malignancy worldwide. Several variant histologies (VH) have been described in BC with a distinct clinical behavior.

OBJECTIVES

This study aims to assess the prognostic impact of VH in BC, comparing its outcomes to pure urothelial carcinoma PUC in both non-muscle invasive (NMIBC) and muscle-invasive (MIBC) settings.

METHODS

We included patients with primary BC, comparing those with VH with those with PUC, with an age and sex-matched proportion of 1:3, considering stage at diagnosis, recurrence-free, progression-free, and overall survival (OS). A total of 616 patients were included in the study, (460 UC and 151 VH).

RESULTS

After first TURBT, MIBC was present in 99 (64.1%) of patients with VH, and 95 (20.6%) with UC (p<0.001). Concerning NMIBC, we observed higher rates of progression to MIBC amid patients with VH (p=0.009). Nodal involvement (p=0.020) and metastatic disease (p<0.001) were significantly higher within the VH group. A higher OS was observed among patients with NMIBC of PUC (p<0.001). There were no statistically significant differences of metastasis-free survival and OS between VH and UC groups within the MIBC setting.

CONCLUSION

We confirmed that VH presents a more aggressive clinical course compared to PUC. An earlier radical treatment within the NMIBC setting could increase the oncological outcomes of the VH patients.

Adjuvant Chemotherapy and Survival After Radical Cystectomy in Histologic Subtype Bladder Cancer

OBJECTIVES

Patients with histologic subtype bladder cancer (HSBC) suffer worse outcomes than those with conventional urothelial carcinoma (UC). We sought to characterize the use of adjuvant chemotherapy (AC) in HSBC after radical cystectomy (RC) using the National Cancer Database (NCDB).

MATERIALS AND METHODS

We retrospectively queried the NCDB (2006-2019) for patients with non-metastatic bladder cancer (BC) who underwent RC (N = 45,797). Patients were stratified by histologic subtype and receipt of AC. Multivariable logistic regression determined associations of demographic and clinicopathologic features with receipt of AC. Multivariable Cox regression evaluated associations between receipt of any AC and overall survival (OS).

RESULTS

We identified 4,469 patients with HSBC classified as squamous, adenocarcinoma, small cell, sarcomatoid, micropapillary, or plasmacytoid. Squamous comprised 31% of the HSBC cohort, followed by small cells and micropapillary. Black patients were presented with a higher prevalence of adenocarcinoma (119/322, 37.0%). Use of AC was highest in plasmacytoid and small cell (30% each) and lowest in squamous (11%). Neuroendocrine histology was independently associated with greater odds of receiving AC (HR 1.6, 95% CI 1.37-1.87), while squamous cell histology was associated with lower odds (HR 0.61, 95% CI 0.53-0.71). On multivariable Cox regression analysis, treatment with AC was associated with significantly longer OS (HR 0.69, 95% CI 0.59-0.81) and for squamous, sarcomatoid, and micropapillary cohorts after stratified by subtype.

CONCLUSIONS

AC was variably used among patients with HSBC and was associated with OS benefit in such patients.

Evaluation of histological variants of upper tract urothelial carcinoma as prognostic factor after radical nephroureterectomy

PURPOSE

To evaluate the impact of variant histology on patients with upper tract urothelial carcinoma (UTUC) survival outcomes.

MATERIALS AND METHODS

A total of 519 patients underwent radical nephroureterectomy without neoadjuvant therapy for UTUC at a single institution between May 2003 and December 2019. Multivariate Cox regression analysis evaluated the impact of variant histology on progression-free survival (PFS), cancer-specific survival (CSS), and overall survival (OS).

RESULTS

Among 84 patients (16.2%) with variant histology, the most frequent variant type was squamous cell differentiation (64.3%), followed by glandular differentiation (25.0%) and sarcomatoid variant (2.4%). They showed pathologically advanced T stage (for ≥ T3, 59.5% vs 33.3%, p < 0.001), higher tumor grade (96.4% vs 85.7%, p = 0.025), and higher rates of lymph node metastasis (17.9% vs 7.8%, p = 0.015), angiolymphatic invasion (41.7% vs 25.7%, p = 0.003), tumor necrosis (57.1% vs 29.0%, p < 0.001) and positive surgical margin (13.1% vs 5.7%, p = 0.015). On multivariate Cox regression analyses, variant histology was significantly associated with worse PFS (hazard ratio [HR] 2.23; 95% confidence interval [CI] 1.55-3.21; p < 0.001), CSS (HR 2.67; 95% CI 1.35-5.30; p = 0.005) and OS (HR 2.22; 95% CI 1.27-3.88; p = 0.005). In subgroup analysis, no significant survival gains of adjuvant chemotherapy occurred in patients with variant histology.

CONCLUSIONS

Variant histology was associated with adverse pathologic features and poor survival outcomes. Our results suggest that patients with variant histology may require a close follow-up schedule and novel adjuvant therapy other than chemotherapy postoperatively.

Efficacy of Platinum-based Chemotherapy in Patients With Metastatic Urothelial Carcinoma With Variant Histology

BACKGROUND/AIM

Variant urothelial carcinoma (VUC, defined herein as urothelial carcinoma with any histological variant) is frequently observed at an advanced stage. However, the efficacy of systemic chemotherapy against VUC in metastatic disease has rarely been reported. This study assessed the therapeutic response and survival outcomes of platinum-based chemotherapy as first-line treatment in patients with metastatic VUC.

PATIENTS AND METHODS

We retrospectively analyzed consecutive patients with metastatic bladder and upper urinary tract cancer who received gemcitabine plus cisplatin (or carboplatin) at the University of Occupational and Environmental Health Hospital between November 2008 and November 2022. Progression-free survival and overall survival were evaluated using the Kaplan-Meier method and Cox proportional hazard models.

RESULTS

Out of 131 patients recorded, 86 (65.6%) had pure urothelial carcinoma (PUC) and 45 (34.4%) had VUC. The most common variant element was squamous differentiation (44.4%). Compared to those with PUC, patients with VUC showed a comparable objective response rate (33.3% vs. 41.9%, p=0.451) and disease control rate (64.5% vs. 75.6%, p=0.221). They also had poorer progression-free survival (median=4.9 months vs. 7.9 months, p=0.014) and overall survival (median=10.9 months vs. 18.2 months, p=0.037) than those with PUC. On multivariate analysis, VUC was an independent predictor of progression (hazard ratio=1.79; 95% confidence interval=1.19-2.69; p=0.005) and mortality (hazard ratio=1.64; 95% confidence interval=1.08-2.48; p=0.020).

CONCLUSION

Although the response of metastatic VUC to platinum-based chemotherapy was not inferior to that of PUC, VUC had progressed faster than PUC. VUC was significantly associated with a poor prognosis after platinum-based chemotherapy as first-line treatment.

Impact of variant histology on upstaging and survival in patients with nonmuscle invasive bladder cancer undergoing radical cystectomy

INTRODUCTION

Variant histology (VH) of urothelial carcinoma is uncommon and frequently presents at the muscle-invasive stage. VH is considering a significant risk factor for progression among patients with nonmuscle invasive bladder cancer (NMIBC). While there is some debate, expert opinion is generally that upfront radical cystectomy (RC) should be consider for these patients. Limited data exists to support this position. In this study, we sought to examine the rate of upstaging and overall survival for patients with VH NMIBC against patients with pure urothelial NMIBC who underwent RC, to help clarify the optimal treatment strategy for these patients.

METHODS

The institutional REDCap database was utilized to identify all patients with T1 and Ta bladder cancer that underwent RC over the study period (2004-2022). Matched-pair analysis was performed between patients with VH and pure urothelial NMIBC; 42 pairs were matched on prior intravesical therapy, presence of muscularis propria on transurethral resection of bladder tumor (TURBT), any carcinoma in situ presence on prior TURBTs, and final tumor staging on TURBT. The primary outcomes of interest were pathologic tumor upstaging rate at RC and overall survival. Secondary outcomes of interest included association of demographic or pretreatment variables with upstaging, and upstaging rates for specific variant histologies.

RESULTS

Patients with VH NMIBC undergoing RC were upstaged at a significantly higher rate than a matched cohort of patients with pure urothelial NMIBC (73.8% vs. 52.4%, P = 0.0244) and among those upstaged, had significantly higher rates of pT3 to pT4 (54.7% vs. 23.8%, P = 0.0088). Rate of node positivity at RC for VH NMIBC was also higher compared to pure urothelial NMIBC (40.5% vs. 21.4%, P = 0.0389). Among histologic variants, patients with plasmacytoid and sarcomatoid subtypes demonstrated the highest rates of upstaging; differences were not statistically significant. The overall median survival was 28.4 months for patients with VH after RC compared to 155.1 months for patients with pure urothelial NMIBC (P = 0.009).

CONCLUSION

Patients with VH NMIBC undergoing RC are at significantly higher risk of upstaging at RC when compared to patients with pure urothelial NMIBC and have worse overall survival. While this study supports the concept of an aggressive treatment approach for patients with VH NMIBC, improvements in understanding of the disease are necessary to improve outcomes.

Survival impact of variant histology in patients with upper tract urothelial carcinoma after radical nephroureterectomy

OBJECTIVE

To investigate the prognostic impact of variant histology (VH) on survival outcomes in upper tract urothelial carcinoma (UTUC) patients after radical nephroureterectomy (RNU).

MATERIALS AND METHODS

Data from 635 UTUC patients who underwent RNU at our institution from May 2003 to June 2019 were retrospectively acquired and analyzed. After propensity score matching (PSM), we investigated the impact of VH on overall survival (OS) and cancer-specific survival (CSS) by using cumulative incidence plots with the log-rank test, Cox regression models, and competing risk regression models.

RESULTS

Overall, 121 (19.1%) patients were diagnosed with VH, including 68 (10.7%) with squamous cell differentiation (SCD) and 28 (4.4%) with adenocarcinoma differentiation (AD). After PSM, the presence of VH was significantly associated with worse OS (HR 1.70, 95% CI 1.25-2.32) and CSS (HR 1.64, 95% CI 1.17-2.31) only in locally advanced UTUC patients (pT>2). In the subgroup analysis, SCD revealed inferior outcomes (OS: HR 1.81, 95% CI 1.28-2.57; CSS: HR 1.73, 95% CI 1.18-2.54) compared with pure urothelial carcinoma (pUC), whereas AD conferred comparable outcomes. In addition, compared with pUC patients, SCD patients with extensive squamous components had significantly decreased OS (HR 4.17, 95% CI 1.84-9.44) and CSS (HR 1.10, 95% CI 0.61-1.99), whereas those with regional squamous components had similar survival outcomes.

CONCLUSION

For UTUC patients after RNU, the presence of VH is associated with aggressive clinicopathological features and inferior survival outcomes. However, the survival outcomes of localized UTUC patients (pT≤2) with VH, and patients with the AD or regional SCD subtype are comparable to those of patients with pUC.

Oncologic outcomes of intravesical therapy in the management of nonmuscle invasive bladder cancer with variant histology

PURPOSE

There is limited data on oncologic outcomes in nonmuscle invasive bladder cancer (NMIBC) with variant histology (VH) managed with intravesical therapy. We sought to evaluate oncologic outcomes for this cohort at a high-volume center.

MATERIALS AND METHODS

A retrospective review of an IRB-approved bladder cancer database was performed. Patients with a history of NMIBC with VH present on transurethral resection of bladder tumor (TURBT) treated with intravesical therapy (BCG or chemotherapy) were identified. Outcomes of interest included recurrence within the bladder, progression to muscle-invasive bladder cancer (MIBC), metastatic progression, cancer-specific, and overall survival. Survival time was computed from the date of initiation of intravesical therapy to the date of event or censoring. For patients who underwent radical cystectomy, recurrence-free, cancer-specific, and overall survival were also computed. The Kaplan-Meier method with log rank was utilized to compare survival time between VH sub-groups.

RESULTS

Ninety patients were included in the final cohort with a median follow-up of 38 months. The majority of patients had T1 disease (72%) and received intravesical BCG (83%) as their only form of intravesical therapy. The most commonly represented VH in this series were glandular and squamous differentiation (26%). Forty-eight patients (53%) experienced recurrence within the bladder with a median recurrence-free survival of 24 months (95% Confidence Interval [CI]: 2-46 months). Five-year rates of progression to MIBC and distant metastasis were both 14% respectively. Twenty-six patients (28%) eventually required cystectomy. When stratifying by VH, patients with sarcomatoid, plasmacytoid, and micropapillary had significantly worse oncologic outcomes.

CONCLUSION

In this series of highly-selected patients with NMIBC and VH, bladder-sparing treatment with intravesical therapy demonstrated acceptable oncologic outcomes for most VHs. This may be an acceptable treatment option for patients without plasmacytoid, sarcomatoid, or micropapillary features who are not suitable cystectomy candidates or who prioritize bladder-sparing treatment.

Clinicopathologic and Survival After Cystectomy Outcomes in Squamous Cell Carcinoma of the Bladder

BACKGROUND

Squamous cell carcinoma of the bladder (SqCC) is a rare disease with limited management data. Thus, we sought to characterize the clinicopathologic and survival outcomes amongst patients with SqCC and explore the association of squamous differentiation within urothelial carcinoma (UC w/Squam), as compared to muscle invasive pure UC.

METHODS

We conducted a single-center retrospective cohort study of patients, stratified by histology, who underwent cystectomy for MIBC. Baseline clinicopathologic characteristics were compared, and overall survival was assessed using Kaplan-Meier method.

RESULTS

We identified 1,034 patients; 37 (3.58%) with SqCC histology, 908 (87.81%) with UC histology, and 89 (8.61%) with UC w/ Squam histology. Among SqCC patients, a higher proportion were Black and similarly a higher proportion were women; amongst patients with UC w/ Squam a higher proportion had lower BMI; and amongst patients with UC a higher proportion had lower clinical (c) T, cN, pathological (p) T, and pN stages. Patients presenting with UC were more likely to receive intravesical therapy; patients presenting with SqCC were less likely to receive neoadjuvant chemotherapy (NAC). Adjuvant chemotherapy rates were similar. With post-hoc Bonferroni analysis, overall survival, cancer-specific survival, and recurrence-free survival were significantly worse for the UC w/ Squam cohort.

CONCLUSIONS

UC w/ Squam histology was associated with worse survival outcomes after cystectomy for muscle invasive bladder cancer compared to UC. Our results suggest that UC w/ Squam is associated with more advanced disease compared to UC, warranting further prospective work on consideration of combination therapies for patients with this disease state.

Metastatic Bladder Cancer Expression and Subcellular Localization of Nectin-4 and Trop-2 in Variant Histology: A Rapid Autopsy Study

BACKGROUND

Nectin-4 and Trop-2 are transmembrane targets of FDA-approved antibody-drug conjugates (ADC) Enfortumab-vedotin (EV) and Sacituzumab govitecan (SG), respectively, for the treatment of metastatic urothelial carcinoma (mUC). The expression and role of Nectin-4 and Trop-2 in mUC variant histology is poorly described.

MATERIALS AND METHODS

We evaluate membranous and cytoplasmic protein expression, and mRNA levels of Nectin-4 and Trop-2 within matched primary and metastatic mUC samples to determine heterogeneity of ADC targets in mUC variants.

RESULTS

Patients with mUC were consented for rapid autopsy immediately after death. Tissues from matched primary and metastatic lesions were collected. A total of 67 specimens from 20 patients were analyzed: 27 were UC, 17 plasmacytoid (PUC), 18 UC with squamous differentiation (UCSD), and 5 neuroendocrine (NE); 10 from primary and 57 from metastatic sites. All histology except NE expressed moderate-high levels of Nectin-4 and Trop-2 by both immunohistochemistry and RNAseq. Nectin-4 demonstrated prominent cytoplasmic staining in metastatic PUC and UCSD. Trop-2 demonstrated strong cytoplasmic and membrane staining in primary and metastatic tumors. Interestingly, Nectin-4 and Trop-2 expression are positively correlated at both mRNA and protein levels.

CONCLUSION

UC and non-NE variants express notable level of Nectin-4 and Trop-2 in both primary and metastatic lesions. Membrane staining of Nectin-4 and Trop-2 is present but cytoplasmic staining is a more common event in both mUC and mUC variant histology. These findings support evaluation of EV and SG in heavily treated variant histology BC and urge attention on the clinical relevance of cytoplasmic localization of ADC targets.

Patient and tumor characteristics of histological subtypes of renal cell carcinoma and its risk of upstaging to ≥pT3

OBJECTIVE

To explore how histological subtypes impact upstaging to nonorgan confined renal cell carcinoma (≥pT3 RCC) in patients treated with partial/radical nephrectomy for cT1-2 RCC.

MATERIALS AND METHODS

We relied on an institutional tertiary-care database to identify RCC patients treated with partial/radical nephrectomy between January 2002 and December 2021. Patients were stratified according to histological subtype of RCC. Upstaging was defined as any cT1-2 tumor classified as ≥pT3 at final pathology. Uni- and multivariable logistic regression models were fitted to predict upstaging.

RESULTS

Of overall 1,020 surgically treated RCC patients, 743 harbored clear-cell (72.8%) vs. 193 (18.9%) papillary vs. 49 (4.8%) chromophobe vs. each 4 (0.4%) collecting duct and sarcomatoid vs. 27 (2.6%) other/mixed pathology of RCC. Median tumor size ranged from 3.0 cm (mixed RCC) to 7.7 cm (sarcomatoid RCC). In total, upstaging rate to ≥pT3 was 22% and ranged from 6.1% (chromophobe RCC) to 75% (collecting duct RCC). In univariable logistic regression models, chromophobe and papillary histological subtypes were significantly associated with lower upstaging of all cT1-2 RCC tumors. After controlling for patient and tumor characteristics in multivariable logistic regression models, papillary RCC independently lowers the risk of upstaging, even in sensitivity analyses for cT1 RCC only.

CONCLUSION

Important differences between histological subtypes of RCC exist regarding characteristics such as stage and tumor size at presentation, as well as upstaging to ≥pT3 at final pathology. Specifically, papillary RCC is significantly associated with lower chance of upstaging even after controlling for confounding parameters. The study is limited by missing central pathological/radiographic review and lack of survival analyses.

The prognostic significance of histologic variant on survival outcomes in patients with metastatic urothelial carcinoma receiving immune checkpoint inhibitor therapy

BACKGROUND

While the treatment guidelines have been established for pure urothelial carcinoma (pUC), patients with variant type urothelial carcinoma (vUC) face limited effective treatment options. The effectiveness of immune checkpoint inhibitors (ICI) in patients with vUC remains uncertain and necessitates additional research.

METHOD

We conducted a retrospective, multicenter study to explore the effectiveness of ICI in patients with pUC or vUC in Taiwan. We evaluated the overall response rate (ORR) through univariate logistic regression analysis and examined the overall survival (OS) and progression-free survival (PFS) using Kaplan-Meier analysis. Additionally, we employed univariate and multivariate Cox proportional hazards models to analyze the data.

RESULT

A total of 142 patients (116 pUC, 26 vUC) were included in our final analysis. The ORR was marginally higher in patients with pUC compared to those with vUC (34.5% vs. 23.1%, p = 0.26). Among all patients, 12.9% with pUC achieved a complete response (CR) after ICI treatment, while no vUC cases achieved CR (p = 0.05). There were no significant differences in PFS (median 3.6 months vs. 4.1 months, p = 0.34) or OS (median 16.3 months vs. 11.0 months, p = 0.24) when comparing patients with pUC or vUC. In the subgroup analysis, patients with pUC who underwent first-line ICI treatment exhibited significantly improved OS compared to those with vUC (24.6 months vs. 9.1 months, p = 0.004).

CONCLUSION

The use of ICI as monotherapy is a feasible and effective treatment approach for patients with metastatic vUC.

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.

Variant histology in upper tract carcinomas: Analysis of the National Cancer Database

INTRODUCTION

Upper urinary tract malignancies are relatively uncommon, with the majority representing urothelial carcinoma (UC). Variant histology (VH) is rare but has been increasingly shown to confer worse prognoses, and standardized approaches to treatment for upper tract cancers with VH have not been established. Our study aimed to analyze outcomes amongst various treatment modalities for upper tract malignancies based on VH subtype. Additionally, we stratified mortality outcomes associated with the upper tract tumors based on their primary location in the renal pelvis (RP) versus ureter.

METHODS

The National Cancer Database was queried for patients who were diagnosed with upper tract malignancy of the RP or ureter from 2005 to 2016. Populations were grouped based on tumor location (RP vs. ureter) and substratified based on tumor histology (UC vs. VH). Cox regression (CR) was used for multivariable survival analysis.

RESULTS

A total of 63,826 patients with upper tract malignancies met inclusion criteria: 36,692 (57.5%) cases involving the RP and 27,134 (42.5%) cases involving the ureter. VH was noted in 2.5% of all tumors with the squamous cell variant being the most common subtype (62.5%). VH presented with higher stage, increased mortality, and higher proportion of metastatic disease relative to UC.  Patients with VH were less likely to undergo surgical intervention and more likely to receive radiation or adjuvant chemotherapy. Neoadjuvant chemotherapy was not associated with tumor downstaging for VH. On multivariable CR, receiving definitive surgical excision improved survival for patients with any VH, and chemotherapy improved survival for patients with renal VH. On subanalysis of CR by VH subtype, survival benefits for surgery were significant for adenocarcinoma, neuroendocrine, and squamous in a renal location and adenocarcinoma, neuroendocrine, sarcoma, and squamous in a ureteral location. Additionally, benefits of chemotherapy were significant for adenocarcinoma in a renal location and neuroendocrine in a ureteral location.

CONCLUSION

Patients with upper tract VH are more likely to present at advanced stages and experience higher mortality rates when compared to pure UC. Generally, survival benefits are seen with either surgical excision or chemotherapy for renal VH and with surgical excision for ureteral VH, but mortality rates for these treatment modalities differ amongst specific subtypes.

A Large Contemporary Experience of Renal Tumors in Young: Clinico-pathological Profile and Long-Term Survival Patterns

Renal tumors in young population are relatively rare. We reviewed our experience with renal masses in patients below 45 years of age. Our objective was to analyze clinico-pathological and survival characteristics of renal malignancy in young adults in contemporary era. The medical records of patients below 45 years of age who underwent surgery for renal mass at our tertiary care center between 2009 and 2019 were retrospectively analyzed. Pertinent clinical information was compiled, including age, gender, year and type of surgery, histopathology and survival data. A total of 194 patients who underwent nephrectomy for suspicious renal masses were included. Mean age was 35.5 (14-45) years and males were 125 (64.4%). A total of 29/198 (14.6%) specimens had benign disease. In addition, 155 (91.7%) out of 169 malignant tumors were renal cell carcinomas, clear cell variant being the most common type (51%). Compared to RCC, non-RCC tumors were more common in females (27.7 vs 78.6%, p < 0.0001), had an early age of diagnosis (27.2 vs 36.9 year, p < 0.00001) and poorer progression-free (58.3 vs 72.0%, p = 0.03) and overall survival (63.6 vs 84.2%, p = 0.02) at 6 years of follow-up. Renal masses in young adults are most commonly RCC but can also include other diverse types. RCC in young adults is usually organ confined and has good prognosis. As compared to RCC, non-RCC malignant tumors occur in young age, are more in females, and have worse prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13193-022-01643-2.

Cancer specific mortality in patients with collecting duct vs. clear cell renal carcinoma

BACKGROUND

Collecting duct carcinoma (CDC) is biologically more aggressive than clear cell renal cell carcinoma (ccRCC). We tested for differences in cancer specific mortality (CSM) rates according to CDC vs. ISUP (International Society of Urological Pathology) 4 ccRCC histological subtype. We hypothesized that the survival disadvantage still applies, even after most detailed adjustments.

METHODS

Within Surveillance, Epidemiology, and End Results database (2004-2018), we identified 380 CDC vs. 6273 ISUP 4 ccRCC patients of all stages. Propensity score matching (age, sex, race/ethnicity, T, N, and M stages, nephrectomy, and systemic therapy status), Kaplan-Meier plots and multivariable Cox regression models were used.

RESULTS

All 380 CDC were matched (1:2) with 760 ISUP4 ccRCC patients. Prior to matching CDC patients exhibited higher rates of lymph node invasion (37.6 % vs. 14.7 %, p < 0.001), and of distant metastases (40.8 % vs. 30.4 %, p < 0.001). Systemic therapy rates were higher in CDC (29.5 % vs. 20.5 %, p < 0.001). However, nephrectomy rates were higher in ISUP4 ccRCC patients (97.5 % vs. 84.7 %, p < 0.001). After matching, in multivariable Cox regression models addressing CSM, CDC was associated with a HR of 1.5 (p < 0.001) in the overall population vs. 1.9 (p = 0.014) in stage I-II vs. 1.4 (p = 0.022) in stage III vs. 1.6 in stage IV (p < 0.001), relative to ISUP4 ccRCC.

CONCLUSION

CDC patients exhibited 40-90 % higher CSM than their ISUP4 ccRCC counterparts in the overall analysis, as well as in stage specific analyses. The CSM disadvantage applies despite higher rates of systemic therapy in CDC patients.

Diagnostic Value of the Vesical Imaging-Reporting and Data System in Bladder Urothelial Carcinoma with Variant Histology

The value of the Vesicle Imaging-Reporting and Data System (VI-RADS) in the diagnosis of muscle-invasive bladder cancer (MIBC) for urothelial carcinoma with variant histology (VUC) remains unknown. We retrospectively evaluated 360 consecutive patients with bladder cancer (255 pure urothelial carcinoma [PUC] and 69 VUC) who underwent multiparametric magnetic resonance imaging between 2011 and 2019. VI-RADS scores assigned by four readers were significantly higher for the VUC group than for the PUC group (p < 0.05). In the cohort of 122 pair-matched patients, there was no significant difference in VI-RADS score distribution between the PUC and VUC groups for all readers (p > 0.05). The area under the receiver operating characteristic curve for MIBC diagnosis via overall VI-RADS score was 0.93-0.94 for PUC and 0.89-0.92 for VUC, with no significant difference between the PUC and VUC groups (p = 0.32-0.60). These data suggests that VI-RADS scores achieved high diagnostic performance for detection of muscle invasion in both PUC and VUC. PATIENT SUMMARY: The Vesical Imaging-Reporting and Data System (VI-RADS) is a standardized system for reporting on detection of muscle-invasive bladder cancer via magnetic resonance imaging (MRI) scans. Our study shows that VI-RADS is also highly accurate for diagnosis for different variants of muscle-invasive bladder cancer, with good inter-reader agreement.

Collecting duct carcinoma: Epidemiology, clinical characteristics and survival

INTRODUCTION

Collecting duct carcinoma (CDC) is a rare renal malignancy. We relied on a large population-based cohort to address epidemiology, clinical characteristics, and treatment of CDC patients. We also tested survival in the overall cohort, as well as in stage-specific fashion.

MATERIALS AND METHODS

Within Surveillance, Epidemiology, and End Results (2004-2018) database, we identified 399 CDC patients. Based on Kaplan-Meier plots survival estimates, conditional survival rates were derived according to disease stage. Cox regression models tested for predictors of cancer specific mortality (CSM).

RESULTS

Overall, 273 (68.4%) patients were male, 236 (59.2%) had T3-4 stages, 148 (37.1%) had lymph node invasion, and 156 (39.1%) had distant metastases at initial diagnosis. Nephrectomy alone was commonest in stage I-II (n = 91/99, 92%) and III (n = 94/116, 81%). Combination of both nephrectomy and systemic therapy was commonest in stage IV (n = 62/172, 36%). In the overall cohort, median cancer specific survival was 18 months. Provided a disease-free interval of 24 months, five-year Kaplan-Meier estimated survival at diagnosis increased from 74.2 to 91.0% in stage I-II, from 31.1 to 65.3% in stage III, and from 6.3 to 34.1% in stage IV. In multivariable Cox regression models addressing CSM, systemic therapy (Hazard Ratio [HR]: 0.47, P = 0.020), nephrectomy (HR: 0.37, P < 0.001) and combination of both (HR: 0.28, P < 0.001) exhibited a strong protective effect.

CONCLUSION

Despite its highly aggressive phenotype and dismal survival, CDC is sensitive to nephrectomy and/or systemic therapy. Moreover, even for advanced stage, a more favorable prognosis can be achieved in patients, who benefit of disease-free interval after diagnosis and initial treatment.

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.

Survival Outcomes After Immediate Radical Cystectomy Versus Conservative Management with Bacillus Calmette-Guérin Among T1 High-grade Micropapillary Bladder Cancer Patients: Results from a Multicentre Collaboration

BACKGROUND

Literature lacks clear evidence regarding the optimal treatment for non-muscle-invasive micropapillary bladder cancer (MPBC) due to its rarity and the presence of only small sample size and single-centre studies.

OBJECTIVE

To assess cancer-specific mortality (CSM) and overall mortality (OM) between immediate radical cystectomy (RC) and conservative management among T1 high-grade (HG) MPBC.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively analysed a multicentre dataset including 119 T1 HG MPBC patients treated between 2005 and 2019 at 15 tertiary referral centres. The median follow-up time was 35 mo (interquartile range: 19-64).

INTERVENTION

Patients underwent immediate RC versus conservative management with bacillus Calmette-Guérin.

OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS

Cumulative incidence functions and Kaplan-Meier methods were applied to estimate survival outcomes. Multivariable Cox analyses were performed to assess independent predictors of disease recurrence and disease progression after conservative management; covariates consisted of pure MPBC, concomitant lymphovascular invasion (LVI), and carcinoma in situ at initial diagnosis.

RESULTS AND LIMITATIONS

Immediate RC and conservative management were performed in 27% and 73% of patients, respectively. CSM and OM did not differ significantly among patient treated with immediate RC versus conservative management (Pepe-Mori test p = 0.5 and log-rank test p = 0.9, respectively). Overall, 66.7% and 34.5% of patients experienced disease recurrence and disease progression after conservative management, respectively. At multivariable Cox analyses, concomitant LVI was an independent predictor of disease recurrence (p = 0.01) and progression (p = 0.03), while pure MPBC was independently associated with disease progression (p = 0.03). The absence of a centralised re-review and the retrospective design represent the main limitations of our study.

CONCLUSIONS

Conservative management could achieve satisfactory results among T1 HG MPBC patients with neither pure MPBC nor LVI at initial diagnosis.

PATIENT SUMMARY

Bacillus Calmette-Guérin seems to be an effective therapy for T1 micropapillary bladder cancer patients with neither pure micropapillary disease nor lymphovascular invasion at initial diagnosis.

Accuracy and prognostic value of radiological lymph node features in variant histologies of bladder cancer

Purpose

To provide first evidence of lymph node (LN) staging using CT scan and its prognostic value in variant histologies of bladder cancer. This knowledge may optimize patient management with variant histologies based on CT morphological findings.

Methods

Preoperative CT scans of patients with variant histologies who underwent RC between 2004 and 2019 were reanalyzed by two independent radiologists in a blinded review process. Specificity, sensitivity, and accuracy for LN staging as well as LN characteristics were evaluated. Correlation with survival was investigated by Kaplan–Meier method, log-rank test and multivariate analysis.

Results

1361 patients with primary tumor of the bladder underwent RC, of which 163 (12%) patients revealed variant histologies. 65 (47.8%) patients have shown an urothelial variant (UV) and 71 (52.2%) a non-urothelial variant (NUV). LN metastases were found in 18 (27.7%) patients with UV and 21 (29.6%) patients with NUV. The accuracy to detect LN metastasis for all variant histologies was 62% with a sensitivity of 46% and a specificity of 70%. Subgroups of UV and NUV revealed an accuracy of 67% and 57%. An increased number of regional LN (HR 2.8; 1.34–6.18) and the loss of fatty hilum (HR 0.36, 0.17–0.76) were prognostic parameters. In multivariate analysis, a fatty hilum (HR 0.313, 0.104–0.945) and the presence of lymph node metastases (HR 2.866, 1.140–7.207) were prognostic.

Conclusion

This first study on CT morphological behavior of variant histologies revealed an accuracy of UV and NUV comparable to UC with low specificity for all variant histologies. CT scan prior RC should be interpreted in regard to histological subtypes.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-022-04010-6.

T1 bladder carcinoma with variant histology: pathological features and clinical significance

The aim of the study was to stratify high-grade T1 (HGT1) bladder urothelial carcinoma into risk categories based on the presence of variant histology when compared to conventional urothelial carcinoma. The clinicopathological features of 104 HGT1 cases of urothelial carcinoma of the bladder with variant histology present in 34 (37%) were assessed. The endpoint of the study was disease-free survival and cancer-specific survival. Overall, variant histology was identified as a significant predictor of disease-free survival (P = 0.035). The presence of any specific variant histology (squamous, glandular, micropapillary, nested, microcystic, inverted growth, villous-like, basaloid, and lymphoepithelioma-like) was identified as a significant predictor of disease-free survival (P = 0.008) and cancer-specific survival (P = 0.0001) in HGT1 bladder cancer. Therefore, our results support including micropapillary HGT1 urothelial carcinoma within the aggressive high-risk category, as suggested by some recent clinical guidelines, but also favor nested, glandular, and basaloid to be placed in the high-risk category due to their potential of aggressive, life-threatening behavior and their limited response to bacillus Calmette-Guerin therapy. Conversely, the low-risk category would include urothelial carcinomas with squamous, inverted growth, or microcystic morphology, all with limited life-threatening potential and good response to current therapy. A very low-risk category would finally include patients whose tumors present villous-like or lymphoepithelioma-like morphology. In conclusion, our findings support the value of reporting the variant histology as a feature of variable aggressiveness in HGT1 urothelial carcinoma of the bladder.

First-line pazopanib in patients with advanced non-clear cell renal carcinoma: An Italian case series

BACKGROUND

Non-clear cell (ncc) metastatic renal-cell carcinoma (RCC) has dismal results with standard systemic therapies and a generally worse prognosis when compared to its clear-cell counterpart. New systemic combination therapies have emerged for metastatic RCC (mRCC), but the pivotal phase III trials excluded patients with nccRCC, which constitute about 30% of metastatic RCC cases.

AIM

To provide a piece of real-life evidence on the use of pazopanib in this patient subgroup.

METHODS

The present study is a multicenter retrospective observational analysis aiming to assess the activity, efficacy, and safety of pazopanib as first-line therapy for advanced nccRCC patients treated in a real-life setting.

RESULTS

Overall, 48 patients were included. At the median follow-up of 40.6 mo, the objective response rate was 27.1%, the disease control rate was 83.3%, and the median progression-free survival and overall survival were 12.3 (95% confidence interval [CI]: 3.6-20.9) and 27.7 (95%CI: 18.2-37.1) mo, respectively. Grade 3 adverse events occurred in 20% of patients, and no grade 4 or 5 toxicities were found.

CONCLUSION

Pazopanib should be considered as a good first-line option for metastatic RCC with variant histology.

Gene Expression Profiling of Muscle-Invasive Bladder Cancer With Secondary Variant Histology

OBJECTIVES

To determine the potential impact of the presence of secondary variant histology on the gene expression profiles of muscle-invasive bladder cancer (MIBC) tumors.

METHODS

For six tumors, revised samples were collected from urothelial and secondary variant components (cohort A). The commercial cohort (cohort B) consisted of the anonymized gene expression profiles of 173 patients with MIBC. Samples were obtained from the clinical use of the Decipher Bladder test that were available as part of the Decipher GRID prospective registry (NCT02609269). Secondary variant presence in cohort B was abstracted from institutional pathology reports. For the commercial cohort, only the urothelial carcinoma component was profiled.

RESULTS

Molecular subtyping of both urothelial and variant components found micropapillary and nested cases were classified as a luminal subtype. Conversely, the sarcomatoid and small cell cases were classified as basal/squamous or neuroendocrine-like, respectively. For cohort B, 50 (29%) of 173 cases had reported secondary variant histology. Cases with squamous variant had basal profiles, small cell cases expressed neuronal markers, and micropapillary cases were classified as luminal. Sarcomatoid tumors had robust epithelial-mesenchymal transition marker expression.

CONCLUSIONS

Our data suggest that in MIBC with secondary variant, the urothelial component can demonstrate an expression profile that closely resembles the variant component.

Temporal trends, tumor characteristics and stage-specific survival in penile non-squamous cell carcinoma vs. squamous cell carcinoma

PURPOSE

To compare Cancer-specific mortality (CSM) in patients with Squamous cell carcinoma (SCC) vs. non-SCC penile cancer, since survival outcomes may differ between histological subtypes.

METHODS

Within the Surveillance, Epidemiology and End Results database (2004-2016), penile cancer patients of all stages were identified. Temporal trend analyses, cumulative incidence and Kaplan-Meier plots, multivariable Cox regression and Fine and Gray competing-risks regression analyses tested for CSM differences between non-SCC vs. SCC penile cancer patients.

RESULTS

Of 4,120 eligible penile cancer patients, 123 (3%) harbored non-SCC vs. 4,027 (97%) SCC. Of all non-SCC patients, 51 (41%) harbored melanomas, 42 (34%) basal cell carcinomas, 10 (8%) adenocarcinomas, eight (6.5%) skin appendage malignancies, six (5%) epithelial cell neoplasms, two (1.5%) neuroendocrine tumors, two (1.5%) lymphomas, two (1.5%) sarcomas. Stage at presentation differed between non-SCC vs. SCC. In temporal trend analyses, non-SCC diagnoses neither decreased nor increased over time (p > 0.05). After stratification according to localized, locally advanced, and metastatic stage, no CSM differences were observed between non-SCC vs. SCC, with 5-year survival rates of 11 vs 11% (p = 0.9) for localized, 33 vs. 37% (p = 0.4) for locally advanced, and 1-year survival rates of 37 vs. 53% (p = 0.9) for metastatic penile cancer, respectively. After propensity score matching for patient and tumor characteristics and additional multivariable adjustment, no CSM differences between non-SCC vs. SCC were observed.

CONCLUSION

Non-SCC penile cancer is rare. Although exceptions exist, on average, non-SCC penile cancer has comparable CSM as SCC penile cancer patients, after stratification for localized, locally invasive, and metastatic disease.

Molecular Biology of Bladder Cancer: Potential Implications for Therapy

Recently completed studies provided high-resolution descriptions of the molecular biological characteristics of urothelial bladder cancers. Whole transcriptome messenger RNA expression profiling revealed that they can be grouped into basal and luminal molecular subtypes resembling the ones described in breast cancers. Retrospective DNA sequencing efforts revealed roles for disruption of DNA damage response pathways in response to conventional chemotherapy and immune checkpoint blockade, and completed and ongoing studies indicate that the molecular biological properties of infiltrating host cells dictate also influence therapeutic outcomes. This article reviews these findings and identify gaps in knowledge that represent opportunities for future research.

Non-Muscle Invasive Bladder Cancer with Variant Histology: Biological Features and Clinical Implications

BACKGROUND

The most common bladder cancer (BC) histotype is pure urothelial carcinoma (UC), which may undergo divergent differentiation in some cases. Variant histology (VH) presents along variable morphologies, either single or combined between them or with pure UC. From a clinical standpoint, the vast majority of BC is diagnosed at non-invasive or minimally invasive stages, namely as non-muscle invasive BC (NMIBC). There is a wide range of therapeutic options for patients with NMIBC, according to their clinical and pathological features. However, current risk stratification models do not show optimal effectiveness. Evidence from the literature suggests that VH has peculiar biological features, and may be associated with poorer survival outcomes compared to pure UC.

SUMMARY

In order to describe the biological features and prognostic/predictive role of VH in NMIBC, and to discuss current treatment options, we performed a systematic literature search through multiple databases (PubMed/Medline, Google Scholar) for relevant articles according to the following terms, single and/or in combination: "non-muscle invasive bladder cancer," "variant histology," "micropapillary variant," "glandular differentiation," "squamous differentiation," "nested variant," "plasmacytoid variant," and "sarcomatoid variant." We extracted 99 studies including original articles, reviews, and systematic reviews, and subsequently analyzed data from 16 studies reporting on the outcome of NMIBC with VH. We found that the relative rarity of these forms as well as the heterogeneity in study populations and therapeutic protocols results in conflicting findings overall. Key Messages: The presence of VH should be taken into account when counseling a patient with NMIBC, since it may upgrade the disease to high-risk tumor and thus warrant a more aggressive treatment.

Bladder preserving chemoradiotherapy compared to surgery for variants of urothelial carcinoma and other tumors types involving the bladder: An analysis of the National Cancer Database

PURPOSE

For muscle-invasive bladder cancer, bladder preserving chemoradiotherapy (BPCRT) has shown to be a viable alternative for patients with urothelial carcinoma (UCa). Traditionally bladder cancer with variant histology UCa or other tumors types involving the bladder have worse outcomes and BPCRT has been contraindicated. However, there is limited high level evidence for this recommendation.

MATERIALS/METHODS

The National Cancer Database (NCDB) was queried for all patients with Bladder cancer treated from 2004 to 2015 restricted to clinical stage T2-4, N0, M0 who had variants of UCa or other tumors types involving the bladder (e.g. adenocarcinoma and squamous cell carcinoma). Only patients treated with definitive intent with either radical cystectomy or BPCRT after maximal transurethral tumor resection were analyzed. Propensity-score matching was used.

RESULTS

356 patients had BPCRT and 2093 patients had definitive surgery for muscle-invasive bladder cancer limited to variants of UCa and other tumors types involving the bladder. On multivariable analysis worse prognosis was associated with age >65 years old (HR 1.24, p = 0.004) and T4 disease (HR 1.90, p < 0.001). In propensity score weighted sample, there was no statistical significant difference in OS for patients with BPCRT as compared to cystectomy (p = 0.387) and for neuroendocrine, micropapillary or not otherwise specified histology subgroups there was no significant difference. Patients with adenocarcinoma (HR 1.75) or squamous cell carcinoma (HR 1.49) had worse OS associated with BPCRT compared to surgery.

CONCLUSION

From 2004 to 2015, BPCRT in muscle-invasive bladder cancer was associated with similar overall survival compared to cystectomy in patients with selected variant histology but with worse OS for adenocarcinoma or squamous cell carcinoma specifically. As our study has inherent limitations, these hypotheses require validation in a prospective setting and/or with a larger sample size.

Sarcomatoid variant urothelial carcinoma of the bladder: a systematic review and meta-analysis of the clinicopathological features and survival outcomes

Background

A systematic review and meta-analysis was performed to compare the clinicopathological features and survival outcomes between sarcomatoid variant (SV)-urothelial carcinoma of the bladder (UCB) and conventional UCB (C-UCB).

Methods

A comprehensive search of PubMed, Embase, and Cochrane Library was performed. Endpoints included clinicopathological features and survival outcomes (overall survival [OS], cancer-specific survival [CSS], and progression-free survival [PFS]). The survival benefits of neoadjuvant chemotherapy (NAC) or adjuvant chemotherapy (AC) for SV-UCB also have been studied.

Results

A total of 8 observational studies were included. Patients with SV-UCB had a higher rate of ≥ stage pT3 (odds ratio [OR], 2.06; 95% confidence interval [CI], 1.64–2.59; p < 0.001) and a lower rate of concomitant carcinoma in situ (OR, 0.25; 95% CI, 0.09–0.72; p = 0.010). The other clinicopathological variables were similar between SV-UCB and C-UCB. With unadjusted data, patients with SV-UCB had a significant inferior OS (HR, 1.24; 95% CI, 1.07–1.44; p = 0.004) and CSS (HR, 2.08; 95% CI, 1.63–2.66; p < 0.001). However, after adjusted, SV-UCB had worse OS (HR, 1.41; 95% CI, 0.95–2.08; p = 0.090) and CSS (HR, 1.54; 95% CI, 0.95–2.52; p = 0.080) approaching the borderline of significance. For SV-UCB, NAC (HR, 0.73; 95% CI, 0.51–1.05; p = 0.090) and AC (HR, 0.88; 95% CI, 0.66–1.17; p = 0.370) seemed to have no benefit on OS.

Conclusions

Compared to C-UCB, SV-UCB was associated with more advanced disease and more inferior OS and CSS. NAC and AC had no survival benefit for SV-UCB.

Prognostic value of pretreatment inflammatory markers in variant histologies of the bladder: is inflammation linked to survival after radical cystectomy?

PURPOSE

To investigate differences in standard preoperative inflammatory markers in patients with urothelial carcinoma (UC) and variant histologies undergoing radical cystectomy (RC) and determine its impact on survival.

METHODS

Patients undergoing RC at an academic high-volume center were retrospectively analyzed. Preoperatively taken CRP, leukocytes, hemoglobin (Hb), and thrombocytes were analyzed as routine inflammatory biomarkers. Log-rank tests and Kruskal-Wallis analysis were used to calculate for differences in survival and in blood levels of biomarkers.

RESULTS

886 patients with complete follow-up and UC or variant histology underwent RC at our institution between 2004 and 2019. Although variant histology presents with significantly higher t stage than UC, cancer-specific survival (CSS) of UC (1-year-CSS: 93%) is not significantly different to variant histology of UC with squamous differentiation (UCSD, 1-year-CSS: 81%), squamous cell carcinoma (SCC, 1-year-CSS: 82%), and adenocarcinoma (AC, 1-year-CSS: 81%). In UC, alterations in all biomarkers except leukocytes beyond routine cut-off values were associated with poor survival (p < 0.01), whereas Hb beyond cut-off values are associated with poor prognosis in SCC (p < 0.05). CRP levels are significantly elevated in UCSD and SCC at time of surgery compared to UC (p < 0.05).

CONCLUSION

Inflammatory biomarkers reveal distinctive patterns across UC and variant histologies of bladder cancer. As inflammation might play an important role in cancer progression, further research is warranted to understand those molecular mechanisms and their potential therapeutic impact in variant histology of bladder cancer.

Micropapillary Versus Urothelial Carcinoma of the Urinary Bladder: Stage at Presentation and Efficacy of Chemotherapy Across All Stages-A SEER-based Study

BACKGROUND

Stage-specific guideline recommendations are lacking for chemotherapy in micropapillary carcinoma of the urinary bladder (MCUB).

OBJECTIVE

To test the efficacy of stage-specific chemotherapy for MCUB.

DESIGN, SETTING, AND PARTICIPANTS

Within the Surveillance, Epidemiology and End Results (SEER) registry (2001-2016), we identified patients with MCUB and pure urothelial carcinoma of the urinary bladder (UCUB) of all stages.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Kaplan-Meier survival analyses and multivariate Cox regression models were used to determine cancer-specific mortality (CSM) in addition to power analyses.

RESULTS AND LIMITATIONS

Of 210 491 patients of all stages, 518 (0.2%) harboured MCUB versus 209 973 (99.8%) UCUB. Stage at presentation was invariably higher in MCUB than in UCUB patients. Of the MCUB patients, 223 (43.1%) received chemotherapy versus 42 921 (20.4%) of the UCUB patients. In MCUB patients, chemotherapy improved CSM-free survival significantly in metastatic stage (hazard ratio [HR] 0.36, p = 0.04). Longer median CSM-free survival was also associated with chemotherapy use in addition to radical cystectomy (RC) versus RC alone in non-organ-confined MCUB (HR 0.69, p = 0.2). Additional power analyses revealed an underpowered comparison. Finally, no CSM difference was recorded in organ-confined MCUB according to the use of chemotherapy in addition to RC versus RC alone (HR 0.98, p = 1).

CONCLUSIONS

Stage at presentation was invariably higher in MCUB than in UCUB patients. Very important CSM reduction was associated with chemotherapy use in metastatic MCUB. A promising protective effect of perioperative chemotherapy might also be applicable to non-organ-confined MCUB, but without sufficient statistical power. Conversely, no association was recorded in organ-confined MCUB.

PATIENT SUMMARY

Patients with micropapillary carcinoma of the urinary bladder (MCUB) present in higher tumour stages than those with urothelial carcinoma of the urinary bladder. Chemotherapy for MCUB is effective in metastatic stages, but of no beneficial effect in organ-confined stage. In not-yet-metastatic but already non-organ-confined stages, we did not have enough observations to show a statistically significant protective effect of chemotherapy.

Bladder cancer in patients younger than 40 years: outcomes from the National Cancer Database

PURPOSE

To evaluate the clinical, pathological, and survival outcomes of bladder cancer in patients aged 18-40 years.

METHODS

We identified 362,091 bladder cancer patients from the National Cancer Database between 2004-2013 and compared patients aged 18-40 years to those > 40 years of age with univariate analysis using Chi-square tests. A subset analysis was performed on patients who underwent cystectomy. Multivariable Cox regression was used for overall survival analysis.

RESULTS

Our final analysis included 314,177 patients with 3314 (1.1%) patients aged 18-40 years. Patients aged 18-40 years had a lower male-to-female ratio (2.4 versus 3.0), a greater proportion of low-grade tumors (72.7% versus 48.3%, p < 0.001), non-muscle invasive tumors (90.3% versus 81.2%, p < 0.001), and variant histology (4.0% versus 3.3%, p < 0.001). Similar trends were observed at cystectomy including lower male-to-female ratio in the 18-40 years group (1.7 versus 3.1), a greater proportion of variant histology (25.0% versus 10.0%, p < 0.001); and 53.3% of those younger patients with variant histology were women. Patients aged 18-40 years who underwent cystectomy had a higher proportion of locally advanced disease (pT4 19.2% versus 14.6%, p = 0.004). Multivariable analyses in both cohorts demonstrated that variant histology was a predictor of worse overall survival.

CONCLUSION

The majority of patients aged 18-40 years with bladder cancer present with low-grade, non-muscle-invasive disease associated with better survival. However, a subset of younger patients with a higher proportion of women presents with aggressive bladder cancer which may be partly explained by a higher prevalence of variant histology.

Adjuvant chemotherapy is ineffective in patients with bladder cancer and variant histology treated with radical cystectomy with curative intent

OBJECTIVES

Adjuvant chemotherapy (ACT) is recommended for non-organ-confined bladder cancer (BCa) after radical cystectomy (RC) and pelvic lymph node dissection (PLND), but there are sparse data regarding its specific efficacy in patients with histological variants. The aim of our study was to evaluate the role of ACT on survival outcomes in patients with variant histology in a large multicenter cohort.

MATERIALS AND METHODS

We retrospectively evaluated data of 3963 patients with BCa treated with RC and bilateral PLND with curative intent at several institutions between 1999 and 2018. The histological type was classified into six groups: pure urothelial carcinoma (PUC) or squamous, sarcomatoid, micropapillary, glandular and neuroendocrine differentiation. Multivariable competing risk analysis was applied to assess the role of ACT on recurrence and cancer-specific mortality (CSM) in each histological subtype.

RESULTS

Of the 3963 patients included in the study, 23% had variant histology at RC specimen and 723 (18%) patients received ACT. ACT was found to be significantly associated with reduced risk of recurrence (sub-hazard ratio [SHR]: 0.55, confidence interval [CI] 0.42-0.71, p < 0.001) and CSM (SHR: 0.58, CI 0.44-0.78, p < 0.001) in the PUC only, while no histological subtype received a significant benefit on survival outcomes (all p > 0.05) from administration of ACT. The limitation of the study includes the retrospective design, the lack of a central pathology review and the number of ACT cycles.

CONCLUSION

In our study, the administration of ACT was associated with improved survival outcomes in PUC only. No histological subtype found a benefit in overall recurrence and CSM from ACT.

Neoadjuvant Chemotherapy in Variant Histology Bladder Cancer: Current Evidence

The role of neoadjuvant chemotherapy in variant histology bladder cancers has yet to be validated in randomized control trials. Several case series have reported experience with NAC in the setting of variant histology. PATIENT SUMMARY: We reviewed outcomes for patients with variant histology muscle-invasive bladder cancer who received chemotherapy before cystectomy. Outcomes varied significantly in the current literature. The best outcomes are associated with neoadjuvant chemotherapy (NAC) for small cell variants, while there is potential benefit with the use of NAC for squamous cell and adenocarcinoma variants.

Clinicopathologic analysis of upper urinary tract carcinoma with variant histology

We report on the clinicopathologic features of 115 cases of high-grade urothelial carcinoma of the upper urinary tract with variant histology present in 39 (34%). Variant histology was typically seen in high pathological stage (pT2-pT4) (82%, 32 cases) patients with lower survival rate (70%, 27 cases, median survival 31 months) and consisted in urothelial with one (23%), two (3%), and three or more variants (3%); 4% of cases presented with pure variant histology. Squamous divergent differentiation was the most common variant (7%) followed by sarcomatoid (6%) and glandular (4%), followed by 3% each of micropapillary, diffuse-plasmacytoid, inverted growth, clear cell glycogenic, or lipid-rich. The pseudo-angiosarcomatous variant is seen in 2%, and 1% each of nested, giant-cell, lymphoepithelioma-like, small-cell, trophoblastic, rhabdoid, microcystic, lymphoid-rich stroma, or myxoid stroma/chordoid completed the study series. Loss of mismatch repair protein expression was identified in one case of upper urinary tract carcinoma with inverted growth variant (3.6%). Variant histology was associated to pathological stage (p = 0.007) and survival status (p = 0.039). The univariate survival analysis identified variant histology as a feature of lower recurrence-free survival (p = 0.046). Our findings suggest that variant histology is a feature of aggressiveness in urothelial carcinoma of the upper urinary tract worth it to be reported.

Clinical and pathological characteristics of bladder cancer in post brachytherapy patients

The long-term risk of secondary malignancy is a potential late effect of brachytherapy. However, the time interval, anatomic site and histopathology are not well studied. We sought to characterize the bladder cancers that developed following treatment of prostate cancer with brachytherapy. Between 1998 and 2014, 4570 patients were treated with brachytherapy at the BC Cancer Agency. Out of those, 69 patients subsequently developed bladder cancer, some of which could have been radiation induced. Histology slides were reviewed for all cases, and site and pathologic features were recorded. Cases were classified as luminal and basal subtypes based on GATA3 and CK5/6 immunohistochemistry. Bladder neck and trigone were among the common sites of involvement. Pathologic review of cases showed that 68 % were high-grade, 25 % were muscle-invasive, and 20 % showed variant histology, including small cell carcinoma, sarcomatoid carcinoma, squamous cell carcinoma, and adenocarcinoma. A subgroup of cases more likely to be radiation-induced, based on site and time interval, was associated with increased pathologic stage (pT1 or higher) compared to the other cases (70 % vs 34 %, p = 0.01). In conclusion, the majority of bladder cancers following brachytherapy in this cohort were of high grade and low stage at diagnosis, most of them demonstrating luminal immunophenotype. A significant number of variant histologies are seen, each demonstrating a specific immunophenotype.

Does Variant Histology Change Management of Non-muscle-invasive Bladder Cancer?

A 52-yr-old man, 35 pack-year smoker, is diagnosed with two non-muscle-invasive urothelial tumors, pTa and pT1, the former upstaged to pT1 by a reference pathologist. Two possible treatment strategies include intravesical bacillus Calmette-Guérin (BCG) and/or primary or rescue cystectomy. The importance or even accurate existence of "variant histology" is put into perspective, and whether the reference pathologist's diagnosis of a micropapillary variant requires a real change in treatment strategy is considered. PATIENT SUMMARY: The reference urologist diagnosed two small bladder tumors as two different depths of infiltration: one as pTa and the other (slightly more severe) as pT1. Suspecting a variant, the reference urologist referred to a second pathologist, who upstaged the less severe tumor to T1, with both defined as micropapillary cancer. This presentation discusses removal of the bladder versus a trial of treatment with bladder preservation.

Diagnostic and prognostic roles of CK20 in the pathology of urothelial lesions. A systematic review

Cytokeratin 20 (CK20) is one of the most common immunohistochemical markers in the routine practice of a pathology lab, as biopsies from the urinary tract encompass a wide spectrum of lesions which may pose issues in their detection and classification. In this review, we aim to outline the diagnostic accuracy and prognostic value of CK20 in flat urothelial lesions, papillary non-invasive and invasive urothelial carcinoma, molecular subgroups and variant histology, and we briefly discuss its limitations and potential pitfalls.

Updates on the Genetics and Molecular Subtypes of Urothelial Carcinoma and Select Variants

Urothelial carcinoma is a morphologically and genomically heterogeneous disease that exhibits a wide spectrum of morphologic features and molecular alterations and subtypes. Classic urothelial carcinoma (not otherwise specified) is the most common tumor type that develops in the urinary bladder but many, well-documented, variant histologies are commonly encountered in approximately one-third of invasive urothelial carcinoma, including squamous, glandular, micropapillary, sarcomatoid, small cell/neuroendocrine, clear cell, lymphoepithelioma-like, and plasmacytoid types, among others. In this review, we provide an update on the molecular advances in urothelial carcinoma and some of its variant histologies.

Effect of variant histology presence and squamous differentiation on oncological results and patient's survival after radical cystectomy

OBJECTIVE

To evaluate the effect of variant histology on pathological and survival findings in patients undergoing radical cystectomy due to muscle invasive bladder cancer.

MATERIALS AND METHODS

Data from 146 patients with radical cystectomy performed due to muscle-invasive urothelial carcinoma between January 2006 to November 2016 at our clinic were investigated. The preoperative and postoperative data of patients with variant histology were compared with nonvariant urothelial carcinoma patients. Then of patients with variant histology only those with squamous differentiation (SqD) were compared with nonvariant urothelial carcinoma patients in terms of preoperative, postoperative and survival data.

RESULTS

Of the 146 patients, 23 had carcinoma with variant histology. Of these, 17 had SqD, 4 had glandular differentiation, 1 patient had plasmocytoid variant and 1 patient had sarcomatoid variant. In patients with variant histology, postoperative T stage and upstaging was higher, with no difference observed in terms of overall and cancer-specific survival compared with nonvariant urothelial cancer patients. SqD patients were observed to have higher postoperative T stage compared to nonvariant urothelial cancer patients, with no significant difference observed in terms of survival.

CONCLUSIONS

In cystectomy pathologies, patients with variant histology (especially SqD patients) were observed to have proportionally higher T stage compared to nonvariant urothelial carcinoma; however there were no significant differences for overall survival and cancer-specific survival.

Molecular Subtypes of Bladder Cancer

PURPOSE OF REVIEW

Recent whole genome characterizations of primary human bladder cancers revealed that they can be grouped into "intrinsic" basal and luminal molecular subtypes. Here, we provide an overview of the subtypes and discuss their biological and clinical properties.

RECENT FINDINGS

Basal cancers are characterized by advanced stage and metastatic disease at presentation. They tend to be enriched with squamous and small cell/neuroendocrine features and inactivating mutations and deletions of TP53 and RB1. Basal cancers can be divided into "epithelial" and "mesenchymal" (also known as "claudin low") subsets, and a portion of the latter form a "neuroendocrine/neuronal" subset that is associated with particularly poor survival. Luminal cancers are often enriched with papillary histopathological features and activating mutations in FGFR3, and they can also be divided into additional subsets based on differential stromal cell infiltration, relative genomic instability, and high- versus low-level expression of carcinoma in situ (CIS) gene expression signatures. Importantly, the bladder cancer molecular subtypes display differential sensitivities to neoadjuvant chemotherapy and immune checkpoint blockade, and preliminary data also suggest that they respond differently to radiation with or without hypoxia modulation. Ongoing studies are investigating the relevance of the molecular subtypes to the bladder cancer histopathological variants and to upper tract urothelial cancer. The bladder cancer molecular subtypes were associated with different prognoses and responses to conventional and targeted therapies in retrospective studies. If validated in prospective studies, molecular subtyping will be integrated into bladder cancer clinical management.

Commentary on "Detection and oncological effect of circulating tumor cells in patients with variant urothelial carcinoma histology treated with radical cystectomy."

OBJECTIVES

To investigate for the presence of circulating tumor cells (CTC) in patients with variant urothelial carcinoma of the bladder (UCB) histology treated with radical cystectomy (RC), and to determine their impact on oncological outcomes.

PATIENTS AND METHODS

We, prospectively, collected data of 188 patients with UCB treated with RC without neoadjuvant chemotherapy. Pathological specimens were meticulously reviewed for pure and variant UCB histology. Preoperatively collected blood samples (7.5ml) were analyzed for CTC using the CellSearch system (Janssen, Raritan, NJ).

RESULTS

Variant UCB histology was found in 47 patients (25.0%), most frequently of squamous cell differentiation (16.5%). CTC were present in 30 patients (21.3%) and 12 patients (25.5%) with pure and variant UCB histology, respectively. At a median follow-up of 25 months, the presence of CTC and nonsquamous cell differentiation were associated with reduced recurrence-free survival (RFS) and cancer-specific survival (pairwise P ≤ 0.016). Patients without CTC had better RFS, independent of UCB histology, than patients with CTC with any UCB histology (pairwise P<0.05). In multivariable analyses, the presence of CTC, but not variant UCB histology, was an independent predictor for disease recurrence (hazard ratio = 3.45, P<0.001) and cancer-specific mortality (hazard ratio = 2.62, P = 0.002).

CONCLUSION

CTC are detectable in about a quarter of patients with pure or variant UCB histology before RC, and represent an independent predictor for outcomes, when adjusting for histological subtype. In addition, our prospective data confirm the unfavorable influence of nonsquamous cell-differentiated UCB on outcomes.

Accurate prediction of progression to muscle-invasive disease in patients with pT1G3 bladder cancer: A clinical decision-making tool

PURPOSE

To improve current prognostic models for the selection of patients with T1G3 urothelial bladder cancer who are more likely to fail intravesical therapy and progress to muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

We performed a retrospective analysis of 1,289 patients with pT1G3 urothelial bladder cancer who were treated with transurethral resection of the bladder (TURB) and adjuvant intravesical bacillus-Calmette-Guérin (BCG). Random-split sample data and competing-risk regression were used to identify the independent impact of lymphovascular invasion (LVI) and variant histology (VH) on progression to MIBC. We developed a nomogram for predicting patient-specific probability of disease progression at 2 and 5 years after TURB. Decision curve analysis (DCA) was performed to evaluate the clinical benefit associated with the use of our nomogram.

RESULTS

In the development cohort, within a median follow-up of 51.6 months (IQR: 19.3-92.5), disease progression occurred in 89 patients (13.8%). A total of 84 (13%) patients were found to have VH and 57 (8.8%) with LVI at TURB. Both factors were independently associated with disease progression on multivariable competing-risk analysis (HR: 4.4; 95% CI: 2.8-6.9; P<0.001 and HR: 3.5; 95% CI: 2.1-5.8; P<0.001, respectively). DCA showed superior net benefits for the nomogram within a threshold probability of progression between 5% and 55%. Limitations are inherent to the retrospective design.

CONCLUSIONS

We demonstrated the clinical value of the integration of LVI and VH in a prognostic model for the prediction of MIBC. Indeed, our tool provides superior individualized risk estimation of progression facilitating decision-making regarding early RC.

Rapid recurrence and radiographic progression of sarcomatoid renal cell carcinoma

Sarcomatoid renal cell carcinoma (sRCC) is an aggressive variant of renal cell carcinoma (RCC) that has a significantly lower overall survival. Even after prompt surgical extirpation, this histologic variant progresses rapidly. We present a case of an early recurrence and rapid progression of sRCC despite successful radical resection.

Adjuvant treatment following radical cystectomy for muscle-invasive urothelial carcinoma and variant histologies: Is there a role for radiotherapy?

Comprehensive molecular characterisation of muscle-invasive urothelial carcinoma and variant histological subtypes has led to the identification of recurrent driver mutations that are distinct in these aggressive subgroups of bladder cancer. While distant metastasis dominates as a pattern of relapse following radical cystectomy or chemoradiotherapy, loco-regional control rates are also suboptimal with single modality local treatment, and likewise, harbour equivocal implications on the long-term prognosis of patients. The role of adjuvant radiotherapy for optimising disease control within the pelvis is controversial, with limited evidence to support its efficacy. Herein, we present a stepwise review on adjuvant radiotherapy post-cystectomy; first, discussing the evidence to date supporting the concept that adjuvant radiotherapy is effective in targeting occult metastases within the pelvis, and adds to the benefits of adjuvant chemotherapy. Next, we outlined the principles underlying the definition of radiotherapy target volumes. To conclude, we addressed the need for appropriate patient stratification for treatment intensification, based on existing clinical models and novel molecular indices of aggression in muscle-invasive urothelial cancers and variant histological subtypes.

Impact of High-risk Features and Effect of Neoadjuvant Chemotherapy in Urothelial Cancer Patients with Invasion into the Lamina Propria on Transurethral Resection in the Absence of Deep Muscle Invasion

BACKGROUND

High-risk non-muscle-invasive bladder cancer (NMIBC) that invades into the lamina propria is frequently understaged and is associated with a risk of lymph node metastasis and death.

OBJECTIVE

To identify high-risk features (HRFs) for NMIBC that may identify patients with poorer prognosis who may benefit from neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC).

DESIGN, SETTING, AND PARTICIPANTS

We performed a single-center retrospective review of patients who underwent RC for NMIBC with invasion into the lamina propria between 1995 and 2013. HRFs included hydronephrosis, abnormal examination under anesthesia, lymphovascular invasion, or variant histology.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Pathology at RC, and overall (OS) and disease-specific (DSS) survival were evaluated and analyzed by Fisher's exact test, Student t test, Cox proportional hazards regression analysis, and the Kaplan-Meier method.

RESULTS AND LIMITATIONS

We identified 336 patients with a median follow-up of 130 mo. Of these, 159 (47%) had no HRF, 140 (41.5%) had one HRF, and 37 (11%) had ≥2 HRFs. At RC, patients with ≥2 HRFs had a significantly higher rate of pathologic T stage upstaging and lymph node metastasis (p<0.05). Median OS was 139 mo for those with no HRF, 127 mo for those with one HRF, and 56 mo for those with ≥2 HRF (p=0.0057). HRFs are also associated with a decreased DSS (p=0.0009). Patients with ≥2 HRFs (11/37) who received NAC showed improved OS (21% vs 55% 5-yr OS, p=0.0353) and trended toward an improvement in DSS (25% vs 56% 5-yr OS, p=0.0716) compared with RC alone.

CONCLUSIONS

The presence of ≥2 HRFs in NMIBC invading the lamina propria is associated with worse pathology at RC and a significant decrease in OS and DSS. NAC appears to provide benefit for these patients. Limitations include retrospective design and limited sample size.

PATIENT SUMMARY

The presence of high-risk features in urothelial cancer with invasion into the lamina propria has a worse prognosis that may be mitigated by neoadjuvant chemotherapy.

Predictors of Complete Pathologic Response (pT0) to Neoadjuvant Chemotherapy in Muscle-invasive Bladder Carcinoma

No predictors of a complete pathologic response (pT0) to neoadjuvant chemotherapy (NAC) in muscle-invasive bladder carcinoma have been established. We performed a retrospective analysis of 50 patients to identify potential predictors. Our results showed that the presence of additional transitional cell variants on pathologic examination (mixed tumors) predicted against pT0, suggesting the avoidance of NAC and its morbidity in these patients with mixed tumors.

BACKGROUND

Randomized trials have supported the use of cisplatin-based neoadjuvant chemotherapy (NAC) in muscle-invasive bladder carcinoma (MIBC) owing to the survival advantage, which has correlated with downstaging of the cancer to pT0. Only 30% to 40% of patients receiving NAC have attained a pT0 response at cystectomy; the remaining have either residual disease or progression. We aimed to identify the factors that could predict a pT0 response to NAC.

PATIENTS AND METHODS

Of 336 patients who had undergone robotic cystectomy at our institute from May 2007 to March 2014, we identified 50 patients who had undergone NAC for MIBC. We conducted a retrospective study, dividing these 50 patients into 2 groups, those with and without a pT0. Factors, including age, histologic features, hydronephrosis at initial presentation, and chemotherapy type, were examined by both univariate and multivariate logistic regression analysis.

RESULTS

Of the 50 patients, 14 (28%) had pT0 at cystectomy, 20 (40%) had progressive disease, and 16 (32%) had residual disease. The median age was 67.5 years, the median glomerular filtration rate at presentation was 87.5 mL/min, the patients had undergone a median of 3 NAC cycles, and the median time from the end of chemotherapy to surgery was 4 weeks. The odds of a pT0 response for pure urothelial carcinoma (UC) were approximately 11 times greater relative to cancers with transitional cell variant histologic features or mixed tumors (odds ratio 0.09, 95% confidence interval 0.021-0.380; P = .0011), including squamous, glandular differentiation, small cell, micropapillary, sarcomatoid, nested component, lymphoepithelioma-like, and plasmacytoid variants.

CONCLUSION

The presence of pure UC favored a pT0 response to NAC compared with those with variant histologic features or mixed tumors. These potential predictors warrant prospective validation to allow the ideal selection of patients for NAC.

Urothelial carcinoma with squamous differentiation--the pathologists׳ perspective

Squamous differentiation is the most common variant histology in urothelial carcinoma and may have effects on clinical outcome. Inconsistencies in reporting variant histologies in urothelial carcinoma are well documented. Immunohistochemical and molecular markers may help identify tumors with squamous differentiation beyond light microscopy.