Bladder Cancer: A Comparison Between Non-urothelial Variant Histology and Urothelial Carcinoma Across All Stages and Treatment Modalities

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.

Variant histology is associated with more non-urothelial tract recurrence but less intravesical recurrence for upper tract urothelial carcinoma after radical nephroureterectomy

PURPOSE

To investigate the prognostic impact of variant histology (VH) on oncological outcomes in patients with upper urinary tract urothelial carcinoma (UTUC) who had undergone radical nephroureterectomy (RNU).

PATIENTS AND METHODS

A total of 1239 patients with clinically localized UTUC who underwent RNU at a single institution between January 2005 and June 2020 were included. The VH was reviewed by a uro-pathologist at our institution. The Cox regression model was used to perform multivariate analysis, including VH and other established prognostic factors for post-RNU oncological outcomes (intravesical recurrence [IVR], non-urothelial recurrence, and cancer-specific death).

RESULTS

Of the 1239 patients with UTUC, 384 patients (31%) were found to have VH. Advanced tumor stage, lymph node metastasis, high tumor grade, lymphovascular invasion, open surgery, and renal pelvis had a significantly larger proportion of UTUC with VH compared to pure UTUC (all p < 0.05). VH was an independent prognostic factor associated with less IVR identified by multivariate analysis, more non-urothelial recurrence, and more cancer-specific mortality.

CONCLUSION

Patients with VH account for 31% with UTUC treated with RNU in this cohort. VH was an independent prognostic factor associated with more non-urothelial recurrence and cancer-specific mortality but less IVR.

Trimodal therapy effect on survival in urothelial vs non-urothelial bladder cancer

OBJECTIVE

To address cancer-specific mortality free-survival (CSM-FS) differences in patients with urothelial carcinoma of the urinary bladder (UCUB) vs non-UCUB who underwent trimodal therapy (TMT), according to organ confined (OC: T2N0M0) vs non-organ confined (NOC: T3-4NanyM0 or TanyN1-3M0) clinical stages.

PATIENTS AND METHODS

Within the Surveillance, Epidemiology, and End Results database (2004-2020), we identified patients with cT2-T4N0-N3M0 bladder cancer treated with TMT, defined as the combination of transurethral resection of bladder tumour, chemotherapy, and radiotherapy. Temporal trends described TMT use over time. Kaplan-Meier plots and multivariable Cox regression (MCR) models addressed CSM in UCUB vs non-UCUB according to OC vs NOC stages.

RESULTS

Of 5130 assessable TMT-treated patients, 425 (8%) harboured non-UCUB vs 4705 (92%) who had UCUB. The TMT rates increased for patients with OC UCUB from 92.4% to 96.8% (estimated annual percentage change of 0.4%, P < 0.001), but not in the NOC stages (P = 0.3). In the OC stage, the median CSM-FS was 36 months in patients with non-UCUB vs 60 months in those with UCUB, respectively (P = 0.01). Conversely, in the NOC stage, the median CSM-FS was 23 months both in UCUB and non-UCUB (P = 0.9). In the MCR models addressing OC stage, non-UCUB histology independently predicted higher CSM (hazard ratio 1.45, P = 0.004), but not in the NOC stage (P = 0.9).

CONCLUSION

In OC UCUB, TMT rates have increased over time in a guideline-consistent fashion. Patients with OC non-UCUB treated with TMT showed a CSM disadvantage relative to OC UCUB. In the NOC stage, use of TMT resulted in dismal CSM, regardless of UCUB vs non-UCUB histology.

Identifying Optimal Candidates for Trimodality Therapy among Nonmetastatic Muscle-Invasive Bladder Cancer Patients

(1) Background: This research aims to identify candidates for trimodality therapy (TMT) or radical cystectomy (RC) by using a predictive model. (2) Methods: Patients with nonmetastatic muscle-invasive bladder cancer (MIBC) in the Surveillance, Epidemiology, and End Results (SEER) database were enrolled. The clinical data of 2174 eligible patients were extracted and separated into RC and TMT groups. To control for confounding bias, propensity score matching (PSM) was carried out. A nomogram was established via multivariable logistic regression. The area under the receiver operating characteristic curve (AUC) and calibration curves were used to assess the nomogram's prediction capacity. Decision curve analysis (DCA) was carried out to determine the nomogram's clinical applicability. (3) Results: After being processed with PSM, the OS of the RC group was significantly longer compared with the TMT group (p < 0.001). This remarkable capacity for discrimination was exhibited in the training (AUC: 0.717) and validation (AUC: 0.774) sets. The calibration curves suggested acceptable uniformity. Excellent clinical utility was shown in the DCA curve. The RC and RC-Beneficial group survived significantly longer than the RC and TMT-Beneficial group (p < 0.001) or the TMT group (p < 0.001). However, no significant difference was found between the RC and TMT-Beneficial group and the TMT group (p = 0.321). (4) Conclusions: A predictive model with excellent discrimination and clinical application value was established to identify the optimal patients for TMT among nonmetastatic MIBC patients.

Impact of Variant Histology on Oncological Outcomes in Upper Tract Urothelial Carcinoma: Results From the ROBUUST Collaborative Group

INTRODUCTION

Oncologic implications of variant histology (VH) have been extensively studied in bladder cancer; however, further investigation is needed in upper tract urothelial carcinoma (UTUC). Our study aims to evaluate the impact of VH on oncological outcomes in UTUC patients treated with radical nephroureterectomy (RNU).

METHODS

A retrospective analysis was performed on patients who underwent a robotic or laparoscopic RNU for UTUC using the ROBUUST database, a multi-institutional collaborative including 17 centers worldwide. Logistic regression was used to assess the effect of VH on urothelial recurrence (bladder, contralateral upper tract), metastasis, and survival following RNU.

RESULTS

A total of 687 patients were included in this study. Median (IQR) age was 71 (64-78) years and 470 (68%) had organ confined disease. VH was present in 70 (10.2%) patients. In a median follow-up of 16 months, the incidence of urothelial recurrence, metastasis, and mortality was 26.8%, 15.3%, and 11.8%, respectively. VH was associated with increased risk of metastasis (HR 4.3, P <.0001) and death (HR 2.0, P =.046). In multivariable analysis, VH was noted to be an independent risk factor for metastasis (HR 1.8, P =.03) but not for urothelial recurrence (HR 0.99, P =.97) or death (HR 1.4, P =.2).

CONCLUSION

Variant histology can be found in 10% of patients with UTUC and is an independent risk factor for metastasis following RNU. Overall survival rates and the risk of urothelial recurrence in the bladder or contralateral kidney are not affected by the presence of VH.

The Impact of Variant Histology in Patients with Urothelial Carcinoma Treated with Radical Cystectomy: Can We Predict the Presence of Variant Histology?

Considering the divergent biological behaviors of certain histological subtypes of urothelial carcinoma, it would be of great importance to examine the impact of variant histology and to predict its presence in patients with bladder cancer. A single-center cohort study included 459 patients who underwent radical cystectomy for urothelial carcinoma between 2017 and 2021. Patients were followed up with until July 2022. We compared clinical, laboratory, and histopathologic characteristics and the overall survival between patients with pure urothelial carcinoma and variant histologies. Our results showed that the patients with variant histology were older and preoperatively more frequently had hydronephrosis and higher values of leukocytes and neutrophils. Also, we found a significant association between variant histology and an advanced stage of tumor disease, the presence of lymphovascular invasion, positive surgical margins, and metastases in surgically resected lymph nodes. The number of neutrophils was identified as an independent preoperative predictor of the presence of variant histology after a radical cystectomy. The overall survival of the patients with variant histology was significantly lower compared to the patients with pure urothelial carcinoma. According to our results, the presence of variant histology represents a more aggressive form of the disease. Preoperative neutrophil counts may indicate the presence of variant histology of urothelial carcinoma in patients with bladder cancer.

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.

Partial cystectomy for bladder squamous cell carcinoma with a 10-year follow-up: a case report

Squamous cell carcinoma (SCC) of the bladder is a rare malignancy of the urinary system. It is prone to invasion and metastasis in the early stage and has a poor prognosis. This case reports a 65-year-old female patient with SCC of the bladder who was free of disease recurrence and metastasis 10 years after partial cystectomy (PC) combined with left ureteral reimplantation. The treatment plan and admission of this patient were retrospectively analyzed in order to provide some reference significance for the treatment plan for the SCC of the bladder.

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.

Adenocarcinoma of the Bladder: Assessment of Survival Advantage Associated With Radical Cystectomy and Comparison With Urothelial Bladder Cancer

PURPOSE

To evaluate the association between radical cystectomy (RC) and cancer-specific mortality (CSM) in patients diagnosed with adenocarcinoma of the bladder (ACB). Moreover, to directly compare the survival advantage of RC between ACB vs. urothelial bladder cancer (UBC).

MATERIALS AND METHODS

Non-metastatic muscle-invasive ACB and UBC patients were identified within Surveillance, Epidemiology, and End Results database (SEER 2000-2018). All analyses were stratified between RC vs. no-RC, in either organ-confined (OC: T2N0M0) or non-organ-confined (NOC: T3-4N0M0 or TanyN1-3M0) stages. Propensity score matching (PSM), cumulative incidence plots, competing risks regression (CRR) analyses, and 3 months' landmark analyses were performed.

RESULTS

Overall, 1,005 ACB and 47,741 UBC patients were identified, of whom 475 (47%) and 19,499 (41%) were treated with RC, respectively. After PSM, comparison between RC vs. no-RC applied to 127 vs. 127 OC-ACB, 7,611 vs. 7,611 OC-UBC, 143 vs. 143 NOC-ACB, and 4,664 vs. 4,664 NOC-UBC patients. 36-month CSM rates in RC vs. no-RC patients were 14 vs. 44% in OC-ACB, 18 vs. 39% in OC-UBC, 49 vs. 66% in NOC-ACB, and 44 vs. 56% in NOC-UBC patients. In CRR analyses, the effect of RC on CSM yielded a hazard ratio of 0.37 in OC-ACB, of 0.45 in OC-UBC, of 0.65 in NOC-ACB and of 0.68 in NOC-UBC patients (all P values<0.001). Landmark analyses virtually perfectly replicated the results.

CONCLUSIONS

In ACB, regardless of stage, RC is associated with lower CSM. The magnitude of this survival advantage was greater in ACB than in UBC, even after control for immortal time bias.

The Effect of Sex on Disease Stage and Survival after Radical Cystectomy in Non-Urothelial Variant-Histology Bladder Cancer

BACKGROUND

Female sex in patients treated by radical cystectomy (RC) is associated with more advanced stage and worse survival. However, studies supporting these findings mostly or exclusively relied on urothelial carcinoma of the urinary bladder (UCUB) and did not address non-urothelial variant-histology bladder cancer (VH BCa). We hypothesized that female sex is associated with a more advanced stage and worse survival in VH BCa, similarly to that of UCUB.

MATERIALS AND METHODS

Within the SEER database (2004-2016), we identified patients aged ≥18 years, with histologically confirmed VH BCa, and treated with comprehensive RC. Logistic regression addressing the non-organ-confined (NOC) stage, as well as cumulative incidence plots and competing risks regression addressing CSM for females vs. males, were fitted. All analyses were repeated in stage-specific and VH-specific subgroups.

RESULTS

Overall, 1623 VH BCa patients treated with RC were identified. Of those, 38% were female. Adenocarcinoma (n = 331, 33%), neuroendocrine tumor (n = 304, 18%), and other VH (n = 317, 37%) were less frequent in females but not squamous cell carcinoma (n = 671, 51%). Across all VH subgroups, female patients had higher NOC rates than males did (68 vs. 58%, p < 0.001), and female sex was an independent predictor of NOC VH BCa (OR = 1.55, p = 0.0001). Overall, five-year cancer-specific mortality (CSM) were 43% for females vs. 34% for males (HR = 1.25, p = 0.02).

CONCLUSION

In VH BC patients treated with comprehensive RC, female sex is associated with a more advanced stage. Independently of stage, female sex also predisposes to higher CSM.

Solitary cardiac metastasis of urothelial carcinoma of the urinary bladder with squamous cell differentiation - a rare manifestation

We present a case of bladder cancer with a singular cardiac metastasis. A 51-year-old female patient was referred to our department for painless macrohematuria. We confirmed the diagnosis of muscle-invasive urothelial carcinoma of the urinary bladder with partial squamous cell differentiation. Computed tomography (CT) staging demonstrated a singular cardiac metastasis. Two months after receiving six cycles of chemotherapy control CT scan revealed massive tumour progression. The singular cardiac metastasis size increased to approximately two thirds of right ventricle size. Singular cardiac metastases of urothelial carcinoma are extremely rare and show rapid progression, hence introduction to therapy should not be delayed.

Establishment of an optimized orthotopic bladder cancer model in mice

BACKGROUND

Bladder cancer (BC) is one of the most common malignancies of the genitourinary system. Animal models offer an important tool to explore tumour initiation, progression, and therapeutic mechanisms. Our aim is to construct an optimized orthotopic BC model which is predictable, reproducible, and convenient.

METHODS

The optimized orthotopic BC model was constructed in male C57BL/6 mice utilizing microsyringes to inoculate them with a murine BC cell line (MB49). Anesthetised mice were inoculated with an MB49 cell suspension (10 µL) at approximately 5 × 10⁶/mL. The whole process of modelling was observed and monitored every 3 days for 21 days utilizing HE staining and transabdominal ultrasonography (TUS).

RESULTS

In this study, the model showed excellent success rates for tumour formation (96.67%) and metastatic rate (89.66%). Compared to the control group (sham operation), mice in the modelling group had serous cachexia, visible haematuresis and weight loss (all P < 0.05). The lungs, liver, ureter and kidneys were found to have tumour metastasis. Moreover, the average survival time (19.73 ± 1.69 d) of modelling mice was significantly shorter than that of the control mice (P < 0.05), which remained alive.

CONCLUSION

Our study established a method using microsyringes to inject murine BC cells into the bladder wall, creating a stable transplantable BC model in mice.

Comparing Pathologic and Survival Outcomes Between Primary and Secondary Muscle Invasive Bladder Cancer when treated by Radical Cystectomy With or Without Neoadjuvant Chemotherapy

OBJECTIVE

To compare pathologic and survival outcomes between primary muscle invasive (pMIBC) and secondary muscle invasive (sMIBC) bladder cancer patients who were treated with or without cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC).

METHODS

We reviewed cT2-T4/N0 MIBC patients at our institution between 2010-2019. pMIBC was defined as presenting with > cT2 disease on initial or restaging TURBT with no prior history of bladder cancer. sMIBC was defined as prior history of NMIBC that was treated with at least one induction course of BCG that progressed to MIBC. Outcomes analyzed included pathologic downstaging rates defined as <pT2/N0, pathologic complete response rates (pT0/N0), and survival outcomes (RFS, CSS, OS). Survival outcomes were analyzed using the Kaplan-Meier Method or Gray's test with log rank. Cox Proportional Hazards and semiparametric hazards models proposed by Fine and Gray were constructed to identify predictors of oncologic outcomes.

RESULTS

333 patients were included in the analysis (sMIBC: 48 vs pMIBC: 285). There were no differences in pathologic downstaging (sMIBC: 54% vs. pMIBC: 51%, p=0.67) or pathologic complete response (sMIBC: 33% vs. pMIBC: 28, p=0.46). Survival analysis showed no differences when patients were treated with NAC+RC in oncologic outcomes. On regression analysis, only >pT2 and N+ disease were predictors of poorer CSS and OS. Separate analysis of sMIBC patients whom underwent RC only (N=61), demonstrated inferior oncologic outcomes to other cohorts (p<0.01).

CONCLUSION

There were no differences in pathologic response or survival between pMIBC and sMIBC patients when managed with NAC and RC.

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.

[Transurethral resection of bladder tumors (TURBT)]

Transurethral resection of bladder tumors (TURBT) is the standard of care for the diagnostics and primary treatment of bladder tumors. These are removed by fragmentation using loop diathermy. The resection area is coagulated for hemostasis. An important aspect is always a complete resection with an adequate amount of detrusor muscle in the specimen. Postoperative intravesical instillation of single-shot chemotherapy has been proven to reduce recurrence rates. Methods for improved tumor visualization (particularly photodynamic diagnostics) are used to enhance tumor detection rates particularly in multifocal tumors or carcinoma in situ (CIS). Thus, recurrence and progression rates can be reduced. Depending on the histological examination of the TURBT specimen, follow-up treatment for non-muscle invasive bladder tumors are adjuvant instillation treatment using chemotherapy or Bacillus Calmette-Guérin (BCG), second look TURBT and early cystectomy or for muscle invasive bladder tumors, radical cystectomy or (oncologically subordinate) trimodal treatment with renewed TURBT, radiotherapy and chemotherapy are indicated. Possible complications of TURBT include bleeding with bladder tamponade, extraperitoneal or intraperitoneal bladder perforation and infections of the urogenital tract.

Oncologic Outcomes of Squamous Cell Carcinoma Versus Urothelial Carcinoma With Squamous Differentiation After Radical Cystectomy for Bladder Carcinoma

INTRODUCTION

In this study we aim to compare clinicopathological characteristics and cancer specific survival between patients treated with radical cystectomy for pure squamous cell carcinoma (SCC) and urothelial carcinoma with squamous differentiation (SqD).

PATIENTS AND METHODS

We reviewed data of 1737 consecutive patients treated with radical cystectomy and urinary diversion between January 2004 and February 2014. Only patients with pure SCC or SqD were included in the analysis. Squamous differentiation was defined as intercellular bridges or keratinization in the tumor. Clinicopathological data and recurrence free survival (RFS) were compared between patients diagnosed with SCC and SqD.

RESULTS

SCC and SqD were found in 318 and 223 patients, respectively. Mean age was 57 ± 8.3 years in SCC and 58.8 ± 7.8 in SqD (P = .008). A higher proportion of female patients was observed in SCC group compared to SqD (31.8% vs. 22% P < .0001). Patients with SqD were more likely to have extravesical (58.3% vs. 46.2%: P = .006) and nodal positive disease (34.5% vs. 14.5%: P < .0001) than pure SCC patients. Bilharzial eggs were found in 61% of SCC vs. 46% of SqD (P = .001).; The median (IQR) follow up period for SCC and SqD was 63 (12-112) months and 23 months (9-74.7), respectively. The 5-year RFS for SCC and SqD were 77% and 59.8 %, respectively (P < .0001).; Multivariate cox regression analysis identified advanced pT stage (OR: 1.9, 95% CI: 1.3-2.86, P = .0001), nodal positive disease (OR: 1.6, 95% CI: 1.1-2.48, P = .01) and SqD histology (OR: 1.6, 95% CI: 1.14-2.31, P = .007 as independent predictors of 5-year RFS.

CONCLUSION

Patient with SCC had significantly higher 5-year RFS in comparison to SqD. The higher rate of extravesical disease and lymph node metastasis in SqD patients is indicative of aggressive behavior of this histologic type.

The effect of neoadjuvant chemotherapy among patients undergoing radical cystectomy for variant histology bladder cancer: A systematic review

Objective

To systematically review the evidence about the effect of neoadjuvant chemotherapy (NAC) for muscle-invasive bladder cancer (MIBC) with pure urothelial carcinoma (pUC) in radical cystectomy (RC) candidates affected by variant histology (VH) bladder cancer.

Methods

A review of the current literature was conducted through the Medline and National Center for Biotechnology Information (NCBI) PubMed, Scopus databases in May 2020. The updated Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed for this systematic review. Keywords used were ‘bladder cancer’, ‘bladder carcinoma’, ‘bladder tumour’ and ‘bladder cancer variants’ and ‘neoadjuvant chemotherapy’. Only original articles in English published after 2000 and reporting oncological outcomes a series of more than five patients with VH were included. We excluded series in which the oncological outcomes of patients with pUC and VH were undistinguishable.

Results

The literature search identified 2231 articles. A total of 51 full-text articles were assessed for eligibility, with 17 eventually considered for systematic review, for a cohort of 450,367 patients, of which 5010 underwent NAC + RC. The median age at initial diagnosis ranged from 61 to 71 years. Most patients received cisplatin-gemcitabine, methotrexate-vinblastine-adriamycin-cisplatin, or carboplatin-based chemotherapy. Only one study reported results of neoadjuvant immunotherapy. The median follow-up ranged from 1 to 120 months. The results showed that squamous cell carcinoma (SCC) is less sensitive to NAC than pUC and that SCC predicts poorer prognosis. NAC was found to be a valid approach in treating small cell carcinoma and may have potential benefit in micropapillary carcinoma.

Conclusions

NAC showed the best oncological outcomes in small cell variants and micropapillary carcinoma, while NAC survival benefit for SCC and adenocarcinoma variants needs further studies. Drawing definite considerations on the efficacy of NAC in VH is complicated due to the heterogeneity of present literature. Present results need to be confirmed in randomised controlled trials.

Sex- and age-related differences in the distribution of bladder cancer metastases

OBJECTIVE

Our objective was to investigate age- and sex-related differences in the distribution of metastases in patients with metastatic bladder cancer.

METHODS

Within the National Inpatient Sample database (2008-2015), we identified 7040 patients with metastatic bladder cancer. Trend test and Chi-square test analyses were used to evaluate the relationship between age and site of metastases, according to sex.

RESULTS

Of 7040 patients with metastatic bladder cancer, 5226 (74.2%) were men and 1814 (25.8%) were women. Thoracic, abdominal, bone and brain metastases were present in 19.5 vs. 23.0%, 43.6 vs. 46.9%, 23.9 vs. 18.7% and 2.4 vs. 2.9% of men vs. women, respectively. Bone was the most common metastatic site in men (23.9%) vs. lung in women (22.4%). Increasing age was associated with decreasing rates of abdominal (from 44.9 to 40.2%) and brain (from 3.2 to 1.4%) metastases in men vs. decreasing rates of bone (from 21.0 to 13.3%) and brain (from 5.1 to 2.0%) metastases in women (all P < 0.05). Finally, rates of metastases in multiple organs also decreased with age, in both men and women.

CONCLUSIONS

The distribution of metastases in bladder cancer varies according to sex. Moreover, differences exist according to patient age and these differences are also sex-specific. In consequence, patient age and sex should be considered in the interpretation of imaging, especially when findings are indeterminate.