Pathology focused review of morphologic subtypes and molecular variants of urothelial carcinoma with an emphasis on clinical/treatment relevance

Urothelial carcinoma (UC) has significant morbidity, mortality, and remains the most financially costly carcinoma to manage and treat. This review will cover special morphologic features of UC that may be noted by the pathologist and any subsequent significance in terms of clinical management or treatment considerations as mentioned or recommended in the latest WHO 2022 classification of GU tumors. Many important potentially therapy altering morphologic findings can be consistently identified and reported on routine microscopic examination of hematoxylin and eosin (H&E) stained slides. Furthermore, there has been a rapid advancement of molecular diagnostics and tailored therapies throughout oncology, and we will briefly highlight some of these as they relate to the management of UC. We will actively attempt to limit the discussion of histologic descriptions or pathologic diagnostic criteria of these entities and focus rather on the recognition of their importance/implication for clinicians who must make clinical management decisions based upon these findings. Finally, the importance of open lines of communication with the pathologists who review clinical specimens as well as their practice and reporting methods cannot be overstated.

Antibody Drug Conjugates in Urological Cancers: A Review of the Current Landscape

PURPOSE OF REVIEW

Our review delves into the progress across urological malignancies and discusses ongoing challenges and future directions in antibody-drug conjugate (ADC) development, emphasising their transformative potential in cancer care.

RECENT FINDINGS

ADCs have advanced from hematologic to solid tumours, notably in breast cancer, and are now pivotal in metastatic urological cancers as both monotherapies and in combination regimens, underscored by the FDA's approval of enfortumab vedotin and sacituzumab govitecan for metastatic urothelial cancer. Progress in metastatic prostate cancer, particularly with ADCs targeting PSMA and STEAP1, is noteworthy, although renal cell cancer presents ongoing challenges. There is a continual search for agents in the metastatic, relapsed testicular cancer landscape. ADCs have emerged as a pivotal innovation in oncology, blending targeted antibody therapy with potent cytotoxic drugs, significantly advancing treatment options for urological malignancies.

Epithelioid malignant peripheral nerve sheath tumor of the bladder and concomitant urothelial carcinoma: A case report

BACKGROUND

Epithelioid malignant peripheral nerve sheath tumor (EMPNST) of the bladder is a rare entity with devastating features. These tumors are thought to originate from malignant transformation of pre-existing schwannomas of pelvic autonomic nerve plexuses, and unlike the conventional malignant peripheral nerve sheath tumor (MPNST), are not associated with neurofibromatosis. The tumor has distinctive morphological, immunohistochemical and molecular features. Additionally, it tends to be more aggressive and have a higher mortality. This is the first case that presents with a synchronous urothelial carcinoma of the bladder and the epithelioid variant of MPNST in the literature. It's also the second reported case of EMPNST originating from the bladder wall.

CASE SUMMARY

In this case report, we present the detailed clinical course of a 71-year-old patient with EMPNST of the bladder alongside a literature review.

CONCLUSION

During the management of EMPNST cases, offering aggressive treatment modalities to the patient, such as radical cystectomy, is appropriate for the best chance to contain the disease, regardless of the tumor stage and the extent of local disease at initial diagnosis.

Precision Medicine in Urothelial Carcinoma: Current Markers to Guide Treatment and Promising Future Directions

OPINION STATEMENT

The treatment landscape for urothelial cancer has changed dramatically in the last 10 years, with the approval of several new treatments. At the same time, profiling of individual tumors has become more commonplace with widespread availability of molecular testing and immunohistochemistry. For urothelial cancer, this has led to current guidelines recommending that molecular testing be obtained in the metastatic setting, and that it be considered in the setting of locally advanced disease. Between molecular testing and immunohistochemistry testing of tumors, the only current guideline-directed application of these tests is in the identification of FGFR3 or FGFR2 alterations for use of FGFR inhibitors. While additional recurrent molecular alterations linked to the pathogenesis of urothelial cancer have been identified, the ability to successfully "drug" the pathways association with such alterations remains limited. There has been extensive research into whether expression of particular proteins might inform specific treatment approaches such as the use of PD-L1 testing to guide immune checkpoint blockade. With the integration of antibody-drug conjugates into the treatment armamentarium for urothelial cancer, ongoing research is seeking to determine whether expression of the targets of these therapies, such as Nectin 4, Trop-2, or HER2, could help to guide treatment.

multiparametric MRI

BACKGROUND

Neoadjuvant chemotherapy (NAC) before radical cystectomy is standard of care in patients with muscle-invasive bladder cancer (MIBC). Response assessment after NAC is important but suboptimal using CT. We assessed MRI without vs. with intravenous contrast (biparametric [BP] vs. multiparametric [MP]) for identifying residual disease on cystectomy and explored its prognostic role.

METHODS

Consecutive MIBC patients that underwent NAC, MRI, and cystectomy between January 2000-November 2022 were identified. Two radiologists reviewed BP-MRI (T2 + DWI) and MP-MRI (T2 + DWI + DCE) for residual tumor. Diagnostic performances were compared using receiver operating characteristic curve analysis. Kaplan-Meier curves and Cox proportional-hazards models were used to evaluate association with disease-free survival (DFS).

RESULTS

61 patients (36 men and 25 women; median age 65 years, interquartile range 59-72) were included. After NAC, no residual disease was detected on pathology in 19 (31.1%) patients. BP-MRI was more accurate than MP-MRI for detecting residual disease after NAC: area under the curve = 0.75 (95% confidence interval (CI), 0.62-0.85) vs. 0.58 (95% CI, 0.45-0.70; p = 0.043). Sensitivity were identical (65.1%; 95% CI, 49.1-79.0) but specificity was higher in BP-MRI compared with MP-MRI for determining residual disease: 77.8% (95% CI, 52.4-93.6) vs. 38.9% (95% CI, 17.3-64.3), respectively. Positive BP-MRI and residual disease on pathology were both associated with worse DFS: hazard ratio (HR) = 4.01 (95% CI, 1.70-9.46; p = 0.002) and HR = 5.13 (95% CI, 2.66-17.13; p = 0.008), respectively. Concordance between MRI and pathology results was significantly associated with DFS. Concordant positive (MRI+/pathology+) patients showed worse DFS than concordant negative (MRI-/pathology-) patients (HR = 8.75, 95% CI, 2.02-37.82; p = 0.004) and compared to the discordant group (MRI+/pathology- or MRI-/pathology+) with HR = 3.48 (95% CI, 1.39-8.71; p = 0.014).

CONCLUSION

BP-MRI was more accurate than MP-MRI for identifying residual disease after NAC. A negative BP-MRI was associated with better outcomes, providing complementary information to pathological assessment of cystectomy specimens.

Artificial intelligence to improve cytology performance in urothelial carcinoma diagnosis: results from validation phase of the French, multicenter, prospective VISIOCYT1 trial

PURPOSE

Cytology and cystoscopy, the current gold standard for diagnosing urothelial carcinomas, have limits: cytology has high interobserver variability with moderate or not optimal sensitivity (particularly for low-grade tumors); while cystoscopy is expensive, invasive, and operator dependent. The VISIOCYT1 study assessed the benefit of VisioCyt® for diagnosing urothelial carcinoma.

METHODS

VISIOCYT1 was a French prospective clinical trial conducted in 14 centers. The trial enrolled adults undergoing endoscopy for suspected bladder cancer or to explore the lower urinary tract. Participants were allocated either Group 1: with bladder cancer, i.e., with positive cystoscopy or with negative cystoscopy but positive cytology, or Group 2: without bladder cancer. Before cystoscopy and histopathology, slides were prepared for cytology and the VisioCyt® test from urine samples. The diagnostic performance of VisioCyt® was assessed using sensitivity (primary objective, 70% lower-bound threshold) and specificity (75% lower-bound threshold). Sensitivity was also assessed by tumor grade and T-staging. VisioCyt® and cytology performance were evaluated relative to the histopathological assessments.

RESULTS

Between October 2017 and December 2019, 391 participants (170 in Group 1 and 149 in Group 2) were enrolled. VisioCyt®'s sensitivity was 80.9% (95% CI 73.9-86.4%) and specificity was 61.8% (95% CI 53.4-69.5%). In high-grade tumors, the sensitivity was 93.7% (95% CI 86.0-97.3%) and in low-grade tumors 66.7% (95% CI 55.2-76.5%). Sensitivity by T-staging, compared to the overall sensitivity, was higher in high-grade tumors and lower in low-grade tumors.

CONCLUSION

VisioCyt® is a promising diagnostic tool for urothelial cancers with improved sensitivities for high-grade tumors and notably for low-grade tumors.

Urinary bladder recurrences following ureteroscopic biopsies of upper tract urothelial cancers: a multi-centre observational study with genomic assessment for clonality

BACKGROUND AND AIMS

Urinary bladder recurrences (UBRs) after radical nephroureterectomy (RNUx) are a known challenge in patients with upper-tract urothelial cancers (UTUCs). We aim to assess factors associated with UBR and clonal-relatedness with resected UTUC.

METHODS

Patients who underwent RNUx for UTUC between 1998 and 2015 in five institutions were identified. Clonal relatedness between primary UTUC and subsequent UBR in a sub-cohort was assessed using next-generation sequencing. A Kaplan-Meier curve was used to assess differences in UBR between two groups (with or without ureteroscopic biopsy).

RESULTS

Of 267 patients with complete records, 73 (27.3%) had UBR during follow-up. The five-year UBR-free survival in all patients was 64.7%. The five-year UBR-free-survival was inferior in patients who underwent URS biopsy compared with patients who did not undergo ureteroscopic biopsy (49.9% vs 76.4%, p < 0.001). History of bladder tumour (HR, 95% CI; 2.94, 1.73-5.00, p < 0.001), ureteroscopic biopsy (HR, 95% CI; 2.21, 1.38-3.53, p = 0.001) and preoperative urine cytology ≥C3 (HR, 95% CI; 2.06, 1.24-3.40, p = 0.005) were independently associated with UBR. Patients with ureteroscopic biopsy (n = 3/5) showed identical mutational changes for common genes (TP53 and FGFR3) between primary UTUC and subsequent UBR.

CONCLUSIONS

Ureteroscopic biopsy of UTUC is a significant risk factor for UBR. Qualitative clonality assessment showed identical mutational signatures between primary UTUC and UBR.

Prognosis of Primary Papillary Ta Grade 3 Bladder Cancer in the Non-muscle-invasive Spectrum

BACKGROUND

Ta grade 3 (G3) non-muscle-invasive bladder cancer (NMIBC) is a relatively rare diagnosis with an ambiguous character owing to the presence of an aggressive G3 component together with the lower malignant potential of the Ta component. The European Association of Urology (EAU) NMIBC guidelines recently changed the risk stratification for Ta G3 from high risk to intermediate, high, or very high risk. However, prognostic studies on Ta G3 carcinomas are limited and inconclusive.

OBJECTIVE

To evaluate the prognostic value of categorizing Ta G3 compared to Ta G2 and T1 G3 carcinomas.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient data for 5170 primary Ta-T1 bladder tumors from 17 hospitals were analyzed. Transurethral resection of the tumor was performed between 1990 and 2018.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Time to recurrence and time to progression were analyzed using cumulative incidence functions, log-rank tests, and multivariable Cox-regression models with interaction terms stratified by institution.

RESULTS AND LIMITATIONS

Ta G3 represented 7.5% (387/5170) of Ta-T1 carcinomas of which 42% were classified as intermediate risk. Time to recurrence did not differ between Ta G3 and Ta G2 (p = 0.9) or T1 G3 (p = 0.4). Progression at 5 yr occurred for 3.6% (95% confidence interval [CI] 2.7-4.8%) of Ta G2, 13% (95% CI 9.3-17%) of Ta G3, and 20% (95% CI 17-23%) of T1 G3 carcinomas. Time to progression for Ta G3 was shorter than for Ta G2 (p < 0.001) and longer than for T1 G3 (p = 0.002). Patients with Ta G3 NMIBC with concomitant carcinoma in situ (CIS) had worse prognosis and a similar time to progression as for patients with T1 G3 NMIBC with CIS (p = 0.5). Multivariable analyses for recurrence and progression showed similar results.

CONCLUSIONS

The prognosis of Ta G3 tumors in terms of progression appears to be in between that of Ta G2 and T1 G3. However, patients with Ta G3 NMIBC with concomitant CIS have worse prognosis that is comparable to that of T1 G3 with CIS. Our results support the recent EAU NMIBC guideline changes for more refined risk stratification of Ta G3 tumors because many of these patients have better prognosis than previously thought.

PATIENT SUMMARY

We used data from 17 centers in Europe and Canada to assess the prognosis for patients with stage Ta grade 3 (G3) non-muscle-invasive bladder cancer (NMIBC). Time to cancer progression for Ta G3 cancer differed from both Ta G2 and T1 G3 tumors. Our results support the recent change in the European Association of Urology guidelines for more refined risk stratification of Ta G3 NMIBC because many patients with this tumor have better prognosis than previously thought.

Five-gene signature for the prediction of response to immune checkpoint inhibitors in patients with gastric and urothelial carcinomas

BACKGROUND

Ample evidence supports the potential of programmed death-ligand 1 (PD-L1) expression, detected by immunohistochemistry, as a predictive biomarker for immunotherapy in patients with advanced cancers. To predict the response to immune checkpoint inhibitors in patients with gastric and urothelial carcinomas, we aimed to replace PD-L1 combined positive score (CPS) with CD274 mRNA in the original four-gene signature and PD-L1 CPS model developed by us.

METHOD

We used quantitative real-time polymerase chain reaction (qRT-PCR) to measure the expression levels of five target genes in a cohort of 49 patients (33 with gastric cancer and 16 with urothelial carcinoma) who had received immunotherapy and whose therapeutic responses were available. The predictive performance was evaluated using R package maxstat.

RESULTS

Cutoff values of mRNA expression level were measured using the log-rank statistics for progression-free survival (PFS). Based on these cutoffs, immunotherapy responses were predicted and sorted into responder (n = 12, 24.5%) and non-responder (n = 37, 75.5%) groups. The median PFS values of predicted responders and non-responders were 14.8 months (95% confidence interval [CI]: 0-34.7) and 4.7 months (95% CI: 1.0-8.4, p = 0.02), respectively. Among the 12 predicted responders, 10 had microsatellite-stable tumors with a low tumor mutational burden. The actual clinical responses (complete and partial) were higher in the responder group than those in the non-responder group: 83.3% and 16.2%, respectively.

CONCLUSION

We modified a predictive biomarker for CD274 mRNA expression to predict the response to immunotherapy in patients with gastric or urothelial carcinomas.

T1G1 Bladder Cancer: Prognosis for this Rare Pathological Diagnosis Within the Non-muscle-invasive Bladder Cancer Spectrum

BACKGROUND

The pathological existence and clinical consequence of stage T1 grade 1 (T1G1) bladder cancer are the subject of debate. Even though the diagnosis of T1G1 is controversial, several reports have consistently found a prevalence of 2-6% G1 in their T1 series. However, it remains unclear if T1G1 carcinomas have added value as a separate category to predict prognosis within the non-muscle-invasive bladder cancer (NMIBC) spectrum.

OBJECTIVE

To evaluate the prognostic value of T1G1 carcinomas compared to TaG1 and T1G2 carcinomas within the NMIBC spectrum.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient data for 5170 primary Ta and T1 bladder tumors from 17 hospitals in Europe and Canada were analyzed. Transurethral resection (TUR) was performed between 1990 and 2018.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Time to recurrence and progression were analyzed using cumulative incidence functions, log-rank tests, and multivariable Cox regression models stratified by institution.

RESULTS AND LIMITATIONS

T1G1 represented 1.9% (99/5170) of all carcinomas and 5.3% (99/1859) of T1 carcinomas. According to primary TUR dates, the proportion of T1G1 varied between 0.9% and 3.5% per year, with similar percentages in the early and later calendar years. We found no difference in time to recurrence between T1G1 and TaG1 (p = 0.91) or between T1G1 and T1G2 (p = 0.30). Time to progression significantly differed between TaG1 and T1G1 (p < 0.001) but not between T1G1 and T1G2 (p = 0.30). Multivariable analyses for recurrence and progression showed similar results.

CONCLUSIONS

The relative prevalence of T1G1 diagnosis was low and remained constant over the past three decades. Time to recurrence of T1G1 NMIBC was comparable to that for other stage/grade NMIBC combinations. Time to progression of T1G1 NMIBC was comparable to that for T1G2 but not for TaG1, suggesting that treatment and surveillance of T1G1 carcinomas should be more like the approaches for T1G2 NMIBC in accordance with the intermediate and/or high risk categories of the European Association of Urology NMIBC guidelines.

PATIENT SUMMARY

Although rare, stage T1 grade 1 (T1G1) bladder cancer is still diagnosed in daily clinical practice. Using individual patient data from 17 centers in Europe and Canada, we found that time to progression of T1G1 cancer was comparable to that for T1G2 but not TaG1 cancer. Therefore, our results suggest that primary T1G1 bladder cancers should be managed with more aggressive treatment and more frequent follow-up than for low-risk bladder cancer.

Urothelial Carcinoma and Prostate-specific Membrane Antigen: Cellular, Imaging, and Prognostic Implications

CONTEXT

Staging, restaging, and surveillance of urothelial carcinoma (UC) is challenging due to suboptimal accuracy of standard of care imaging modalities. Prostate-specific membrane antigen (PSMA) imaging may serve to improve characterisation of UC.

OBJECTIVE

To appraise available literature regarding cellular, imaging, and prognostic implications of PSMA for UC.

EVIDENCE ACQUISITION

A systematic review was performed considering all available literature (including conference abstracts) published from 1990 to 2020 and reported according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines following registration in PROSPERO (CRD42020186744). All relevant texts relating to immunohistochemical analysis and PSMA-based imaging in UC were included and collated. Additionally, FOLH1 (gene encoding PSMA) expression according to The Cancer Genome Atlas (TCGA) database was analysed as well as according to consensus and TCGA molecular classification subtypes and subsequently compared with clinical outcomes.

EVIDENCE SYNTHESIS

PSMA expression across UC tumour tissue was heterogeneous (0-100%) but appeared to decrease with increased grade and stage. The TCGA analysis demonstrated loss of FOLH1 expression with increasing T stage (p = 0.0180) and N stage (p = 0.0269), and reduced FOLH1 expression was associated with worse disease-free survival. PSMA expression in UC neovasculature was variable but mostly increased (44-100%). Eleven reports of PSMA-based imaging for UC were identified, reporting on 18 patients. PSMA positron emission tomography (PET) imaging was positive in 17 out of 18 patients. The included literature review data were limited by mostly low-quality, retrospective studies.

CONCLUSIONS

Tissue PSMA, or FOLH1 expression, may inversely be associated with pathological and survival outcomes in localised UC. PSMA PET imaging may improve detection of metastatic disease and response to systemic therapy due to PSMA expression in neovasculature. Available evidence is limited; thus, larger, prospective studies are required to confirm early results and define populations that benefit most.

PATIENT SUMMARY

In this systematic review, we assess the potential role of prostate-specific membrane antigen in urothelial cancer. We found that its utility is in expression of blood vessels surrounding metastasis. We conclude that it may be beneficial in detecting metastasis and response to systemic therapies.

Survival trends in chemotherapy exposed metastatic bladder cancer patients and chemotherapy effect across different age, sex, and race/ethnicity

PURPOSE

To test for survival differences in metastatic urothelial carcinoma of the urinary bladder (mUCUB) patients, according to years of diagnosis, age, sex, and race/ethnicity over time and for the effect of chemotherapy on overall mortality (OM).

MATERIALS AND METHODS

Within the Surveillance, Epidemiology, and End Results (2000-2016), we identified 6860 mUCUB patients. Of those, 3,249 were exposed to chemotherapy. Kaplan-Meier plots and Cox regression models focused on OM. First, we tested the effect of years of diagnosis (historical [2000-2005] vs. intermediate [2006-2011] vs. contemporary [2012-2016]) in chemotherapy exposed mUCUB patients. Second, we tested the effect of chemotherapy in all mUCUB patients.

RESULTS

In chemotherapy exposed mUCUB patients according to historical vs. intermediate vs. contemporary years, median overall survival was 11 vs. 13 vs. 14 months respectively, which translated into hazard ratios (HR) of 0.86 (P = 0.005) and 0.75 (P < 0.001) in intermediate and contemporary vs. historical, respectively. Subgroup analyses in <70 years old, males and Caucasians were in agreement regarding statistically significant differences between historical vs. intermediate vs. contemporary, respectively. In multivariable Cox regression models fitted in the entire mUCUB cohort, chemotherapy exposure reduced OM (HR: 0.46; P < 0.001). Virtually the same results were recorded in age, sex, and race/ethnicity subgroups analyses.

CONCLUSIONS

Contemporary chemotherapy exposed mUCUB patients exhibited better survival than their historical and intermediate counterparts. Chemotherapy reduced mortality by half, across all patient types.

SEOM-SOGUG clinical guideline for localized muscle invasive and advanced bladder cancer (2021)

Most muscle-invasive bladder cancer (BC) are urothelial carcinomas (UC) of transitional origin, although histological variants of UC have been recognized. Smoking is the most important risk factor in developed countries, and the basis for prevention. UC harbors high number of genomic aberrations that make possible targeted therapies. Based on molecular features, a consensus classification identified six different MIBC subtypes. Hematuria and irritative bladder symptoms, CT scan, cystoscopy and transurethral resection are the basis for diagnosis. Radical cystectomy with pelvic lymphadenectomy is the standard approach for muscle-invasive BC, although bladder preservation is an option for selected patients who wish to avoid or cannot tolerate surgery. Perioperative cisplatin-based neoadjuvant chemotherapy is recommended for cT2-4aN0M0 tumors, or as adjuvant in patients with pT3/4 and or pN + after radical cystectomy. Follow-up is particularly important after the availability of new salvage therapies. It should be individualized and adapted to the risk of recurrence. Cisplatin–gemcitabine is considered the standard first line for metastatic tumors. Carboplatin should replace cisplatin in cisplatin-ineligible patients. According to the EMA label, pembrolizumab or atezolizumab could be an option in cisplatin-ineligible patients with high PD-L1 expression. For patients whose disease respond or did not progress after first-line platinum chemotherapy, maintenance with avelumab prolongs survival with respect to the best supportive care. Pembrolizumab also increases survival versus vinflunine or taxanes in patients with progression after chemotherapy who have not received avelumab, as well as enfortumab vedotin in those progressing to first-line chemotherapy followed by an antiPDL1/PD1. Erdafitinib may be considered in this setting in patients with FGFR alterations. An early onset of supportive and palliative care is always strongly recommended.

Two Patients with Urachal Cancer with Multifocal Adenocarcinoma Recurrences in the Urothelium of the Prostatic and Penile Urethra

We report two cases with recurrences of urachal adenocarcinoma (UrAC) in the urethra. Both patients had mucinous UrAC without metastasis, for which they were treated with en-bloc partial cystectomy and umbilectomy. The first patient developed recurrence of UrAC in the distal urethra after 1 yr. Distal urethrectomy revealed multiple additional recurrences in the penile and prostatic urethra. The patient underwent radical cystoprostatectomy with en-bloc urethrectomy. At 5 mo after surgery, liver metastases were found. A search in our institutional database revealed a second patient who developed a solitary recurrence of UrAC in the prostatic urethra 8 yr after partial cystectomy. Radical cystoprostatectomy was performed. The patient subsequently experienced recurring UrAC in the urethra, which were treated with multiple surgeries and radiation. Unfortunately, local tumor control could not be achieved and the patient developed distant metastases 7 yr after cystoprostatectomy. Our two cases and four comparable cases reported in the literature indicate that urothelial spread of UrAC is rare but possible. It remains to be determined if UrAC spreads along the urothelium similar to urothelial cancer or if these multifocal urethral recurrences were the first sign of local metastasis.

Validation of grading of non-invasive urothelial carcinoma by digital pathology for routine diagnosis

Background

Pathological grading of non-invasive urothelial carcinoma has a direct impact upon management. This study evaluates the reproducibility of grading these tumours on glass slides and digital pathology.

Methods

Forty eight non-invasive urothelial bladder carcinomas were graded by three uropathologists on glass and on a digital platform using the 1973 WHO and 2004 ISUP/WHO systems.

Results

Consensus grades for glass and digital grading gave Cohen’s kappa scores of 0.78 (2004) and 0.82 (1973). Of 142 decisions made on the key therapeutic borderline of low grade versus high grade urothelial carcinoma (2004) by the three pathologists, 85% were in agreement. For the 1973 grading system, agreement overall was 90%.

Conclusions

Agreement on grading on glass slide and digital screen assessment is similar or in some cases improved, suggesting at least non-inferiority of DP for grading of non-invasive urothelial carcinoma.

Gastrocnemius acrometastasis from muscle-invasive urothelial bladder carcinoma: A case report

Urinary bladder carcinoma is a common malignancy worldwide. The metastatic disease to distant organs including lung, liver, and bone is well established. However, metastasis to below-knee-level; also known as acrometastasis is a rare occurrence and occurs approximately 0.1% of all bone metastases. It is standard of care to obtain a contrast enhanced computed tomography scan of the chest, abdomen, and pelvis for pretreatment planning, primary staging, and post treatment disease surveillance. This makes the occurrence of acrometastasis harder to detect and may only manifest clinically in advance disease. We report a case of 55 years old gentleman treated as muscle-invasive bladder urothelial carcinoma, presented with chronic left knee pain, and imaging demonstrating tumor in the left knee region. Histopathologic study shows features of metastatic disease from urinary bladder carcinoma to the left gastrocnemius muscle. The attending physician should raise the suspicion of metastatic disease if the patient with known malignancy presented with new soft tissue lesion elsewhere in the body.

RB1 and TP53 co-mutations correlate strongly with genomic biomarkers of response to immunity checkpoint inhibitors in urothelial bladder cancer

Background

Muscle invasive urothelial bladder carcinoma (MIBC) present RB1 and TP53 somatic alterations in a variable percentage of tumors throughout all molecular subtypes. MIBCs with neuroendocrine features have a high response rate to immunity checkpoint inhibitors (ICIs). Whether the presence of somatic co-alterations in these 2 genes in MIBCs is relevant to their responsiveness to ICIs is not known.

Methods

The potential correlation of different genomic biomarkers of response to ICIs like tumor mutational burden (TMB), single nucleotide variants (SNV) predicted neoantigens, DNA damage response (DDR) genes, DNA somatic signatures and TILs infiltrate was explored in patients with somatic co-alterations in RB1 and TP53 (RB1&TP53) as compared with patients with no alterations in any (double wild type, DWT) or with alterations in just one of the 2 genes. The Cancer Genome Atlas (TCGA) pancancer BLCA dataset of cystectomy specimens (n = 407) with mutation, copy number alterations and transcriptomic (RNA sequencing) data as well as the IMVigor 210 study (n = 348) of metastatic urothelial bladder cancers treated with atezolizumab (PD-L1 inhibitor) with clinical response data containing transcriptomic (RNA sequencing), along with a subset (n = 274) with mutation and copy number data were used for this purpose. A novel tumor microenvironment metascore (TMM) was developed based in a LASSO regularized Cox model with predictive and prognostic ability.

Results

Samples with co-altered RB1&TP53: a) were enriched in immunity effectors (CD8 cytotoxic lymphocytes, NK cells) and display higher scores of a T cell inflamed signature; b) have a higher TMB, higher number of SNV predicted neoantigens and higher TILs fractions; c) have a higher number of DDR mutated and deep deleted DDR genes; d) have DNA somatic signatures 2 and 13 related to APOBEC mutagenesis. Using the IMVigor 210 dataset, RB1&TP53 samples had the highest response rate to atezolizumab and a strong correlation with TMB and TMM. The consensus molecular subtype classification in the IMVigor 210 dataset showed a significant correlation with both the response to treatment (p = 0.001, Chisquare) and the presence of RB1 and TP53 genomic alterations (p < 0.001, Chisquare).

Conclusions

RB1&TP53 co-alterations are strongly associated with genomic biomarkers of response to ICIs in MIBCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08078-y.

Assessment of Xpert Bladder Cancer Monitor test performance for the detection of recurrence during non-muscle invasive bladder cancer follow-up

Purpose

To assess the performance of the Xpert Bladder Cancer (BC) Monitor during the follow-up of patients with non-muscle invasive bladder cancer (NMIBC).

Methods

Patients with previously diagnosed NMIBC and followed up in clinical practice settings in two French urology departments between September 2017 and July 2019 were consecutively enrolled in this prospective observational study. Patients with a positive cystoscopy or computed tomography urogram underwent subsequent transurethral resection of the bladder, and/or biopsy, and the specimens were pathologically assessed. Cytology and Xpert BC Monitor tests were performed on urine samples. Xpert BC Monitor performance was assessed versus cystoscopy for disease-negative patients or versus histology for disease-positive patients, and was compared to that of cytology.

Results

Overall, 500 patients with a median age of 70.0 years were included. NMIBC recurrence was diagnosed in 44 cases (8.8%). Overall sensitivity, specificity, and negative predictive values (NPVs) were 72.7% (32/44), 73.7% (330/448) and 96.5% (330/342) for the Xpert BC Monitor, and 7.7% (2/26), 97.8% (310/317) and 92.8% (310/334) for cytology, respectively. The Xpert BC Monitor detected 92.3% (12/13) of the high-grade tumours and ruled out their presence in 99.7% (330/331) of cases. Analysis of the areas under the receiver operating characteristic curves demonstrated the superior performance of the Xpert BC Monitor over that of cytology.

Conclusion

Xpert BC Monitor performance was superior to that of cytology in the follow-up of NMIBC. The exclusion of aggressive tumours with a very high NPV (99.7%) supports the use of this urinary test in daily practice.

[Penile metastasis from urothelial carcinoma: Review of literature.]

OBJECTIVE

Penile metastasis is a very rare clinical entity. The primary origin is usually genitourinar y followed by the gastrointestinal. MATERIAL AND METHODS: Review of the available literature on a case of penile metastasis of urothelial bladder carcinoma.

RESULTS

Penile metastasis is an exceptional entity despite the rich vascularization of this organ. Less than 500 cases have been described. Most cases manifestas exophytic or nodular lesions. Its association with disseminated disease conditions its palliative management in a large part of the cases, as well as an unfavorable prognosis. In selected cases, surgical treatment can be chosen. CONCLUSIONS: Since its clinical presentation is variable, clinical suspicion is important in the presence of a skin lesion of torpid evolution taking into account the patient's oncological history.

Prognostic Value of the WHO1973 and WHO2004/2016 Classification Systems for Grade in Primary Ta/T1 Non-muscle-invasive Bladder Cancer: A Multicenter European Association of Urology Non-muscle-invasive Bladder Cancer Guidelines Panel Study

BACKGROUND

In the current European Association of Urology (EAU) non-muscle-invasive bladder cancer (NMIBC) guideline, two classification systems for grade are advocated: WHO1973 and WHO2004/2016.

OBJECTIVE

To compare the prognostic value of these WHO systems.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient data for 5145 primary Ta/T1 NMIBC patients from 17 centers were collected between 1990 and 2019. The median follow-up was 3.9 yr.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Univariate and multivariable analyses of WHO1973 and WHO2004/2016 stratified by center were performed for time to recurrence, progression (primary endpoint), cystectomy, and duration of survival, taking into account age, concomitant carcinoma in situ, gender, multiplicity, tumor size, initial treatment, and tumor stage. Harrell's concordance (C-index) was used for prognostic accuracy of classification systems.

RESULTS AND LIMITATIONS

The median age was 68 yr; 3292 (64%) patients had Ta tumors. Neither classification system was prognostic for recurrence. For a four-tier combination of both WHO systems, progression at 5-yr follow-up was 1.4% in low-grade (LG)/G1, 3.8% in LG/G2, 7.7% in high grade (HG)/G2, and 18.8% in HG/G3 (log-rank, p < 0.001). In multivariable analyses with WHO1973 and WHO2004/2016 as independent variables, WHO1973 was a significant prognosticator of progression (p <  0.001), whereas WHO2004/2016 was not anymore (p =  0.067). C-indices for WHO1973, WHO2004, and the WHO systems combined for progression were 0.71, 0.67, and 0.73, respectively. Prognostic analyses for cystectomy and survival showed results similar to those for progression.

CONCLUSIONS

In this large prognostic factor study, both classification systems were prognostic for progression but not for recurrence. For progression, the prognostic value of WHO1973 was higher than that of WHO 2004/2016. The four-tier combination (LG/G1, LG/G2, HG/G2, and HG/G3) of both WHO systems proved to be superior, as it divides G2 patients into two subgroups (LG and HG) with different prognoses. Hence, the current EAU-NMIBC guideline recommendation to use both WHO classification systems remains correct.

PATIENT SUMMARY

At present, two classification systems are used in parallel to grade non-muscle-invasive bladder tumors. Our data on a large number of patients showed that the older classification system (WHO1973) performed better in terms of assessing progression than the more recent (WHO2004/2016) one. Nevertheless, we conclude that the current guideline recommendation for the use of both classification systems remains correct, since this has the advantage of dividing the large group of WHO1973 G2 patients into two subgroups (low and high grade) with different prognoses.

Pre-therapy serum albumin-to-globulin ratio in patients treated with neoadjuvant chemotherapy and radical nephroureterectomy for upper tract urothelial carcinoma

PURPOSE

The accurate selection of patients who are most likely to benefit from neoadjuvant chemotherapy is an important challenge in oncology. Serum AGR has been found to be associated with oncological outcomes in various malignancies. We assessed the association of pre-therapy serum albumin-to-globulin ratio (AGR) with pathologic response and oncological outcomes in patients treated with neoadjuvant platin-based chemotherapy followed by radical nephroureterectomy (RNU) for clinically non-metastatic UTUC.

METHODS

We retrospectively included all clinically non-metastatic patients from a multicentric database who had neoadjuvant platin-based chemotherapy and RNU for UTUC. After assessing the pretreatment AGR cut-off value, we found 1.42 to have the maximum Youden index value. The overall population was therefore divided into two AGR groups using this cut-off (low, < 1.42 vs high, ≥ 1.42). A logistic regression was performed to measure the association with pathologic response after NAC. Univariable and multivariable Cox regression analyses tested the association of AGR with OS and RFS.

RESULTS

Of 172 patients, 58 (34%) patients had an AGR < 1.42. Median follow-up was 26 (IQR 11-56) months. In logistic regression, low AGR was not associated with pathologic response. On univariable analyses, pre-therapy serum AGR was neither associated with OS HR 1.15 (95% CI 0.77-1.74; p = 0.47) nor RFS HR 1.48 (95% CI 0.98-1.22; p = 0.06). These results remained true regardless of the response to NAC.

CONCLUSION

Pre-therapy low serum AGR before NAC followed by RNU for clinically high-risk UTUC was not associated with pathological response or long-term oncological outcomes. Biomarkers that can complement clinical factors in UTUC are needed as clinical staging and risk stratification are still suboptimal leading to both over and under treatment despite the availability of effective therapies.

Developing a Machine Learning Algorithm for Identifying Abnormal Urothelial Cells: A Feasibility Study

INTRODUCTION

Urine cytology plays an important role in diagnosing urothelial carcinoma (UC). However, urine cytology interpretation is subjective and difficult. Morphogo (ALAB, Boston, MA, USA), equipped with automatic acquisition and scanning, optical focusing, and automatic classification with convolutional neural network has been developed for bone marrow aspirate smear analysis of hematopoietic diseases. The goal of this preliminary study was to determine the feasibility of developing a machine learning algorithm on Morphogo for identifying abnormal urothelial cells in urine cytology slides.

METHODS

Thirty-seven achieved abnormal urine cytology slides from cases with the diagnosis of atypical urothelial cells and above (suspicions or positive for UC) were obtained from 1 hospital. A pathologist (J.R.) reviewed the slides and manually selected and annotated representative cells to feed into Morphogo with following categories: benign (urothelial cells, squamous cells, degenerated cells, and inflammatory cells), atypical cells, and suspicious cells. Initial validation of the algorithm was performed on a subset of the original 37 cases. Urine samples from additional 12 unknown cases with various histological diagnoses (6 cases of high-grade urothelial carcinoma (HGUC), 1 case of low-grade urothelial carcinoma (LGUC), 1 case of prostate adenocarcinoma, 1 case of renal cell carcinoma, and 4 cases of non-neoplastic conditions) were collected from another hospital for initial blind testing.

RESULTS

A total of 1,910 benign and 1,978 abnormal (atypical and suspicious) cells from 37 slides were annotated for developing and training of the algorithm. This algorithm was validated on 27 slides that resulted in identification of at least 1 abnormal cell per slide, with a total of 200 abnormal cells, and an average of 7.4 cells per slide. Of the 12 unknown cases tested, the original cytology was positive for tumor cells in 2 HGUC samples. Morphogo was abnormal (atypical or suspicious) for 6 samples from patients with UC, including one with LGUC and one with prostate adenocarcinoma.

CONCLUSION

Morphogo machine learning algorithm is capable of identifying abnormal urothelial cells. Further validation studies with a larger number of urine samples will be needed to determine if it can be used to assist the cytological diagnosis of UC.

GATA3-Positive Adnexal Adenocarcinoma: Report of a Confusing Case with a Potential Pitfall of Leading to a Misdiagnosis of Urothelial Carcinoma and a Review of Published Work

We describe a confusing case of GATA3-positive adnexal adenocarcinoma with a potential pitfall of leading to a misdiagnosis of urothelial carcinoma. A 62-year-old male presented with a subcutaneous nodule on the right lower abdomen around a scar from surgery for urothelial carcinoma in the right urinary tract, which had been resected 8 years previously. Histologically, atypical cells possessing ample cytoplasm and partial intracytoplasmic lumens were densely grouped in the subcutaneous expansive nodule and bilateral inguinal lymph nodes dissected. Decapitation secretion could not be seen. Neoplastic cells were positive for CK7, GATA3, and GCDFP15, and negative for CK5/6, CK20, p63, CD10, PAX8, HER-2, and uroplakin-II. Neoplastic cells in the urothelium and the metastasized lung were positive for CK7, CK5/6, and GATA3, and negative for CK20, p63, GCDFP15, and TTF-1. A variable level of GATA3 expression in malignant tumors with apocrine and eccrine differentiation should be recognized by dermatologists.

Incidence and significance of GATA3 positivity in gallbladder adenocarcinoma

GATA3 immunostaining is a sensitive marker for mammary and urothelial carcinomas. It is routinely used in surgical pathology during workup of carcinomas of unknown origin. To the best of our knowledge, this is the first focused study of GATA3 expression in gallbladder adenocarcinomas. In this study, we evaluated GATA3 expression in 38 gallbladder adenocarcinomas. Eight of 38 (21%) gallbladder adenocarcinomas were positive for GATA3. The expression of GATA3 tended to be moderate to strong when present. It was patchy (<50% positivity) in 4 cases, characterized by discrete clusters or groups of malignant cells with areas of intervening negative tumor cells, whereas it was diffuse (>50% positivity) in the other 4 cases. GATA3 expression did not show any significant correlation with clinicopathologic features such as sex, histologic grade, perineural invasion, vascular invasion, pathologic stage, or distance metastasis. The results of our study show that a subset of gallbladder adenocarcinomas (21%) can be GATA3 positive. Awareness of this phenomenon is important while working up GATA3-positive carcinomas immunohistochemically.

Benign Mimickers of Urinary Bladder Cancer: a Case Series

Bladder cancer is one of the leading malignancies in the world associated with significant morbidity and mortality. However, several benign lesions of the bladder can mimic urothelial carcinoma clinically and radiologically owing to overlapping signs and symptoms. Thus, rendering a correct diagnosis is imperative as it will have a significant impact on the management of patients. We present an amalgamation of five cases having a high suspicion of urothelial malignancy, which were subsequently diagnosed as benign entities with better prognosis and thus warranted a different therapeutic approach.

Randomized Phase III Trial of Dose-dense Methotrexate, Vinblastine, Doxorubicin, and Cisplatin, or Gemcitabine and Cisplatin as Perioperative Chemotherapy for Patients with Muscle-invasive Bladder Cancer. Analysis of the GETUG/AFU V05 VESPER Trial Secondary Endpoints: Chemotherapy Toxicity and Pathological Responses

BACKGROUND

Perioperative chemotherapy (neoadjuvant or adjuvant) has been developed to increase overall survival for nonmetastatic muscle-invasive bladder cancer (MIBC). Retrospective studies or prospective phase II trials have been reported to use dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (dd-MVAC) or gemcitabine and cisplatin (GC). As dd-MVAC has shown higher response rates in metastatic disease, better efficacy is expected in the perioperative setting.

OBJECTIVE

We designed a randomized phase III trial to compare the efficacy of dd-MVAC or GC in MIBC perioperative (neoadjuvant or adjuvant) setting.

DESIGN, SETTING AND PARTICIPANTS

A total of 500 patients were randomized from February 2013 to March 2018 in 28 centers and received either six cycles of dd-MVAC every 2 wk or four cycles of GC every 3 wk.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary endpoint (progression-free survival at 3 yr) was not reported. We focused on secondary endpoints: chemotherapy toxicity and pathological responses.

RESULTS AND LIMITATIONS

In the neoadjuvant group, 218 patients received dd-MVAC and 219 received GC. Of the patients, 60% received six cycles in the dd-MVAC arm and 84% received four cycles in the GC arm; 199 (91%) and 198 (90%) patients underwent surgery, respectively. Complete pathological response (ypT0pN0) was observed in 84 (42%) and 71 (36%) patients, respectively (p=0.2). An organ-confined status (<ypT3pN0) was obtained in 154 (77%) and 124 (63%) patients, respectively (p=0.001). In the adjuvant group, 40% of patients received six cycles in the dd-MVAC arm and 60% received four cycles in the GC arm. Most of Common Terminology Criteria for Adverse Events (CTCAE) grade ≥3 toxicities concerned hematological toxicities, reported for 129 (52%) patients in the dd-MVAC group and 134 (55%) patients in the GC group. Gastrointestinal (GI) grade ≥3 disorders were more frequently observed in the dd-MVAC arm (p=0.003), as well as asthenia of grade ≥3 (p<0.001).

CONCLUSIONS

The toxicity of dd-MVAC was manageable with more severe asthenia and GI side effects than that of GC in perioperative chemotherapy. A higher local control rate (complete pathological response, tumor downstaging, or organ confined) was observed in the dd-MVAC arm (p=0.021). However, such data have to be confirmed on progression-free survival, with primary endpoint data expected in mid-2021.

PATIENT SUMMARY

The authors have designed a randomized phase III controlled study comparing the efficacy of gemcitabine and cisplatin, and dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (dd-MVAC) in patients for whom chemotherapy has been decided, before or after radical cystectomy. Higher toxicity regarding asthenia and gastrointestinal side effects along with a better bladder control rate were observed in the dd-MVAC arm. However, such data have to be confirmed on progression-free survival, with primary endpoint data expected in mid-2021.

Smoke load prognostic impact on bacillus Calmette-Guérin (BCG) treated non-muscle invasive bladder cancer

PURPOSE

Smoking habit is the major risk factor for bladder cancer (BC), related to about 50% of these tumors; however, the tobacco dose-effect impact on BC immune treatment is underexplored. This study evaluates the impact of smoke load on non-muscle invasive bladder cancer (NMIBC) prognosis after intravesical BCG.

METHODS

Smoke load, recurrence, progression and disease-specific survival were evaluated in a retrospective study including NMIBC patients treated with intravesical BCG between 2006 and 2015. Multivariate Cox regression, ROC and Kaplan-Meier curves were utilized.

RESULTS

132 pT1 NMIBC patients were included: 95 (72%) males, mean age 69.6 ± 10.5 years and mean smoking pack-years 22.0 ± 20.8. Recurrence, progression and disease-specific death occurred in 69 (52.3%, mean 20.55 ± 20.44 months), 22 (16.7%, mean 31.39 ± 20.19 months) and 11 (8.3%, mean 37.23 ± 18.34 months), respectively. Smoke load significantly impacted recurrence, HR = 1.019 (95% CI 1.008-1.030, p = 0.0004), and progression, HR = 1.034 (95% CI 1.016-1.052, p = 0.0002), but not survival. For every 1-year increment in pack-years, the risk of relapse and progression increases by 1.9% and 3.4%, respectively. Over 20 pack-year showed the best predictive prognostic power.

CONCLUSION

The smoke load has a potential prognostic role in terms of recurrence and progression in the BCG treated NMIBC. Future studies should explore the smoking impact on the immune system, mainly beyond 20 pack-year.

Invasive plasmacytoid urothelial carcinoma: A comparative study of E-cadherin and P120 catenin

Invasive plasmacytoid urothelial carcinomas (PUCs) are an uncommon aggressive variant, which often shows immunohistochemical loss of E-cadherin, underlying its distinct discohesive histology. The marker P120 (well described in breast pathology as being a diagnostic tool alongside E-cadherin for lobular neoplasia) has not been evaluated in PUCs. Biopsies, transurethral resections, and cystectomies of PUCs were collected, and whole-slide immunohistochemical analysis of E-cadherin and P120 was applied. A subset of cases were also tested for CDH1 mutation. PUC cases were stratified into morphologic categories of classic, pleomorphic, or desmoplastic. For E-cadherin, 24 of 33 (73%) cases showed an abnormal staining pattern, consisting of complete absence of staining (17/24; 71%) or cytoplasmic staining (7/24; 29%). For P120, 24 of 33 (73%) cases showed an abnormal staining pattern, consisting of loss of membranous staining with cytoplasmic reactivity. Only 2 cases showed a discordant E-cadherin/P120 immunoprofile (94% concordance). Significant staining differences among the 3 morphologic categories were not found. CDH1 mutation was found in 4 of 8 (50%) of cases, with 3 of 4 (75%) cases showing matched molecular/immunoprofile reactivity. No cases with CDH1 mutation showed discordant pattern E-cadherin/P120 immunoreactivity. Our rate of aberrant E-cadherin immunoreactivity in PUCs (73%) is similar to a meta-analysis of published cases (74%). We also report an identical rate of aberrant P120 immunoreactivity in PUCs (73%). While PUC remains a histologic diagnosis, in a subset of cases showing a less appreciated pattern (such as desmoplastic) or confounding cytoplasmic E-cadherin reactivity, the utility of paired P120 staining may be a useful diagnostic tool.

Assessing CD 10 Expression Level and Its Prognostic Impact in Egyptian Patients with Urothelial Carcinoma

Background and aim:

CD10 is expressed in urothelial carcinoma cells and cancer associated fibroblasts (CAF). In the current study, CD10 immunohistochemical staining (IHC) and CD10 mRNA expression in urothelial carcinoma of bladder (UCB) were assessed, and its relationship with tumor progression and prognosis was investigated.

Patients and Methods:

In this study, 106 formalin fixed paraffin-embedded (FFPE) tissue of UCB, obtained through radical cystectomy specimen, and 10 matched normal tissue samples were included.CD10 expression was evaluated by immunohistochemistry and real time PCR techniques.

Results:

CD10 expression in tumor cells and associated stromal fibroblasts was significantly associated with high tumor grade and advanced stage. Significant correlation was found between CD10 tumor expression and lymphovascular invasion (LVI) (P<0.001) as well as perineural invasion (PNI). CD10 expression in stromal fibroblasts was significantly associated with squamous differentiation of tumor cells, lymph node metastasis (LNM), and tumor necrosis. Positive CD10 expression in both tumor cells and associated stromal fibroblasts was associated with shorter OS . CD10 mRNA was overexpressed in tumors in comparison with the matched normal tissues. CD10 mRNA was significantly higher in invasive tumor, advanced stage tumor, and high grade tumor. There was significant correlation between CD10 mRNA tumor expression and LVI, PNI, and tumor recurrence.

Conclusion:

Increased expression of CD10 in the tumor and CAF was strongly correlated with tumor progression, invasion, metastasis, shorter OS, and RFS in urothelial carcinoma patients. CD10 mRNA showed significantly higher expression in tumor tissue than in matched normal tissue. CD10 mRNA was associated with depth of invasion, TNM stage, tumor grade, vascular tumor invasion, and tumor recurrence.

Mandibular Metastasis of a Recurrent Poorly Differentiated Urothelial Bladder Carcinoma

Metastatic lesions to the oral cavity are uncommon; they represent between 1 and 3% of all malignant oral neoplasms. In this article, we report a rare case of metastatic urothelial bladder carcinoma in the mandible detected on oral radiographic images and confirmed with multiple imaging modalities. A 67-year-old woman presented to our clinic suffering from pain in the right side of the mandible with a mild swelling. Panoramic radiograph revealed an ill-defined relatively radiolucent lesion in the right mandibular premolar-canine region presenting with permeative changes. Cone-beam computed tomography showed a relatively hypodense lesion with demineralization, interruption of the buccal cortices, and slight thickening and sclerosis of the buccal cortical bone. The patient was referred for further evaluation including additional advanced imaging radiographic techniques (MRI and PET scan) and clinical and histopathological examinations that lead to a final diagnosis of metastatic lesion from an underlying urothelial bladder carcinoma.

Cutaneous metastasis of bladder urothelial carcinoma

Cutaneous metastases of genitourinary malignancies are an extremely rare phenomenon. Few cases of skin metastasis from urothelial carcinoma of the bladder have been reported. We report a case of 71-year-old female with primary bladder transitional cell carcinoma who presented with the initial presentation of cutaneous skin lesions that covered the entire lower abdominal wall.

Contemporary Grading and Staging of Urothelial Neoplasms of the Urinary Bladder: New Concepts and Approaches to Challenging Scenarios

Grading and staging of urothelial neoplasm are the most crucial factors in risk stratification and management; both necessitate optimal accuracy and consistency. Several updates and recommendations have been provided though recent publications of the 4th edition of the World Health Organization classification, the 8th edition of the American Joint Committee on Cancer staging system, and the International Consultation on Urological Diseases-European Association of Urology updates on bladder cancer. Updates and recent studies have provided better insights into and approaches to the challenging scenarios in grading and staging of urothelial neoplasm; however, there remain aspects that need further investigation and refinement.

Epidemiology of Bladder Cancer: A Systematic Review and Contemporary Update of Risk Factors in 2018

CONTEXT

Bladder cancer (BC) is a significant health problem, and understanding the risk factors for this disease could improve prevention and early detection.

OBJECTIVE

To provide a systematic review and summary of novel developments in epidemiology and risk factors for BC.

EVIDENCE ACQUISITION

A systematic review of original articles was performed by two pairs of reviewers (M.G.C., I.J., F.E., and K.P.) using PubMed/Medline in December 2017, updated in April 2018. To address our primary objective of reporting contemporary studies, we restricted our search to include studies from the last 5yr. We subdivided our review according to specific risk factors (PICO [Population Intervention Comparator Outcome]).

EVIDENCE SYNTHESIS

Our search found 2191 articles, of which 279 full-text manuscripts were included. We separated our manuscripts by the specific risk factor they addressed (PICO). According to GLOBOCAN estimates, there were 430000 new BC cases and 165000 deaths worldwide in 2012. Tobacco smoking and occupational exposure to carcinogens remain the factors with the highest attributable risk. The literature was limited by heterogeneity of data.

CONCLUSIONS

Evidence is emerging regarding gene-environment interactions, particularly for tobacco and occupational exposures. In some populations, incidence rates are declining, which may reflect a decrease in smoking. Standardisation of reporting may help improve epidemiologic evaluation of risk.

PATIENT SUMMARY

Bladder cancer is common worldwide, and the main risk factors are tobacco smoking and exposure to certain chemicals in the working and general environments. There is ongoing research to identify and reduce risk factors, as well as to understand the impact of genetics on bladder cancer risk.

Expression of TOMM34 and Its Clinicopathological Correlations in Urothelial Carcinoma of the Bladder

The substantial difference between normal cells and cancer cells in terms of their energy metabolism in mitochondria provides an interesting basis for the development of novel therapeutic agents targeting energy machinery of tumour cells. TOMM34 is one of the Tom (translocase of the outer membrane of mitochondria) family that was found to be overexpressed in colorectal, hepatocellular, lung and early invasive breast carcinomas. The expression profile of mitochondrial translocases in bladder cancer compared to normal urinary bladder tissues has not been investigated yet. Therefore, the aim of the current study is to investigate the expression pattern of TOMM34 in bladder cancer tissues and explore its correlation with the clinico-pathological parameters of those cases. Sixty patients who underwent either transurethral resection or radical cystectomy for bladder cancer were included in this study with revision of all their clinicopathological data and tumor slides. Ten histologically normal urothelial biopsies were also included. Immunohistochemical staining for TOMM34 was done and semi-quantitatively scored using the modified H-score. All relations were analysed using established statistical methodologies. TOMM34 overexpression was significantly associated with high tumour stage, muscle invasion and high grade. Significant positive association was observed between TOMM34 expression and poor outcome in terms of shorter disease-specific survival. This study suggests TOMM34 as a biomarker of progression and poor prognosis in urothelial cell carcinoma patients. Furthermore, we suggest a role played by mitochondrial machinery in urothelial cell carcinoma progression, which is a potential target for the newly-discovered vaccine therapy for urothelial cell carcinoma.

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.

Perioperative chemotherapy for urothelial carcinoma of the upper urinary tract: A systematic review and meta-analysis

INTRODUCTION

Upper tract urothelial carcinomas are rare malignancies with differences in anatomy and biology requiring therapeutic strategies that differ from bladder cancer. The role of perioperative systemic therapy in this disease remains uncertain with limited data to support its use. A systematic review of the literature and meta-analysis was therefore undertaken to provide more information and guide clinical practice.

METHODS

A literature search was performed using Embase and Medline databases with additional searches performed manually using terms associated with upper tract urothelial malignancies. Data was extracted from studies of patients that underwent nephrouretectomy for the management of upper tract urothelial carcinoma and received either neoadjuvant or adjuvant systemic therapy. Overall survival (OS), disease-free survival (DFS), and cancer-specific survival (CSS) were summated and analyzed using Cochrane Revman software Version 5.3.

RESULTS

There were 13 comparative studies and no randomized studies identified for data extraction; 11 adjuvant and 2 neoadjuvant with 1170 patients receiving perioperative systemic therapy and 3472 controls that did not. Perioperative chemotherapy was associated with improved OS (HR 0.75, 95%CI 0.57-0.99), DFS (HR 0.54, 95%CI 0.32-0.92), and CSS (HR 0.69, 95%CI 0.42-1.15).

CONCLUSIONS

The available data suggests that perioperative systemic therapy is associated with improved survival in patients with upper tract urothelial cancer.

Bladder cancer: Present and future

Bladder cancer has a high incidence and involves high associated morbidity and mortality. Since its initial clinical suspicion, early diagnostic confirmation and multimodal treatment involve different medical specialties. For this reason, we consider it important to spread the current consensus for its management. Recent advances in immunology and Chemotherapy make it necessary to expose and reflect on future perspectives.

Bladder urothelial carcinoma extending to rectal mucosa and presenting with rectal bleeding

An 87-year-old-man with prostate-cancer-stage-T1c-Gleason-6 treated with radiotherapy in 1996, recurrent prostate cancer treated with leuprolide hormonal therapy in 2009, and bladder-urothelial-carcinoma in situ treated with Bacillus-Calmette-Guerin and adriamycin in 2010, presented in 2015 with painless, bright red blood per rectum coating stools daily for 5 mo. Rectal examination revealed bright red blood per rectum; and a hard, fixed, 2.5 cm × 2.5 cm mass at the normal prostate location. The hemoglobin was 7.6 g/dL (iron saturation = 8.4%, indicating iron-deficiency-anemia). Abdominopelvic-CT-angiography revealed focal wall thickening at the bladder neck; a mass containing an air cavity replacing the normal prostate; and adjacent rectal invasion. Colonoscopy demonstrated an ulcerated, oozing, multinodular, friable, 2.5 cm × 2.5 cm mass in anterior rectal wall, at the usual prostate location. Histologic and immunohistochemical analysis of colonoscopic biopsies of the mass revealed poorly-differentiated-carcinoma of urothelial origin. At visceral angiography, the right-superior-rectal-artery was embolized to achieve hemostasis. The patient subsequently developed multiple new metastases and expired 13 mo post-embolization. Comprehensive literature review revealed 16 previously reported cases of rectal involvement from bladder urothelial carcinoma, including 11 cases from direct extension and 5 cases from metastases. Patient age averaged 63.7 ± 9.6 years (all patients male). Rectal involvement was diagnosed on average 13.5 ± 11.8 mo after initial diagnosis of bladder urothelial carcinoma. Symptoms included constipation/gastrointestinal obstruction-6, weight loss-5, diarrhea-3, anorexia-3, pencil thin stools-3, tenesmus-2, anorectal pain-2, and other-5. Rectal examination in 9 patients revealed annular rectal constriction-6, and rectal mass-3. The current patient had the novel presentation of daily bright red blood per rectum coating the stools simulating hemorrhoidal bleeding; the novel mechanism of direct bladder urothelial carcinoma extension into rectal mucosa via the prostate; and the novel aforementioned colonoscopic findings underlying the clinical presentation.

Non-invasive papillary urothelial carcinoma of the vagina: molecular analysis of a rare case identifies clonal relationship to non-invasive urothelial carcinoma of the bladder

We present a rare case of non-invasive papillary urothelial carcinoma of the vagina as the initial presentation of a multicentric urothelial carcinoma also involving bladder and renal pelvis and report for the first time in the literature the molecular alterations observed in the vaginal urothelial lesion and the synchronous lesions of the urinary tract. In this case, the non-invasive papillary urothelial carcinoma in the vagina displayed the same genetic alterations in the FGFR3 and PIK3CA genes as those seen in the non-invasive papillary urothelial carcinoma of the bladder contrasting with the wild phenotype observed in the invasive urothelial carcinoma of the renal pelvis. This observation could reinforce the theory of "seeding" of carcinoma cells as a valid and most likely explanation of this multifocality. In addition, we emphasize in this report the importance of recognizing this rare lesion in the female genital tract and its differential diagnosis.

Expression of human epidermal growth factor receptor 2 in bladder urothelial carcinoma

BACKGROUND

Urothelial bladder carcinoma (UBC) is one of the most prevalent cancers in men worldwide. Human epidermal growth factor receptor 2 (HER2) expression has been detected in a wide range of urothelial carcinoma. Despite many reports in the literature, the prognostic significance of this overexpression remains unclear. The aim of this study was to assess the expression of HER2 in urothelial bladder carcinomas and its association with clinical and pathological parameters.

METHODS

103 cases of UBC were diagnosed in our department between January 2014 and December 2015. The tumor specimens obtained by transurethral resection or cystectomy were evaluated by immunohistochemistry using HER2 antibody.

RESULTS

HER2 protein overexpression was present in 11.7% of cases and associated with tumor grade (p = 0.003) and pathological stage (p = 0.015). In multivariate analysis, HER2 overexpression was associated only with tumor grade (P = 0.04).

CONCLUSION

HER2 protein overexpression is noted in patients with high grade cancer. This expression may select patients for anti HER2 targeted therapy. Future larger and prospective studies will verify the frequency of HER2 alteration and the role of HER2 in the aggressive behavior.

Utility and pitfalls of GATA3 immunocytochemistry for diagnosis of metastatic breast carcinoma and urothelial carcinoma on cytology specimens

INTRODUCTION

Although GATA3 expression has been studied extensively on histology specimens and has demonstrated a high level of accuracy in detecting carcinomas from breast or urothelial origin, its utility on cytology samples, especially the influence of different sample (fine-needle aspiration [FNA] versus effusion fluid) and preparation (cell block versus smear) on the staining, is understudied.

MATERIALS AND METHODS

We retrospectively searched our institution's pathology database for cytologic cases where GATA3 immunostaining was performed during diagnostic workup and identified a total of 178 cases, consisting of 89 metastatic breast carcinomas, 22 metastatic urothelial carcinomas, and 67 malignant neoplasms of other origin. Frequency of GATA3 expression was evaluated in each group.

RESULTS

For metastatic breast carcinomas, 75% expressed GATA3; 74% on FNA samples and 77% on fluid samples; 71% on cell block and 89% on smear. GATA3 was positive in 44% triple-negative breast carcinomas. Of the 22 metastatic urothelial carcinomas (21 FNA samples and 1 fluid; 21 cell blocks and 1 smear), all were positive for GATA3. Of the 67 malignancies of other origin, 4 (6%) were positive for GATA3 (ie, a metastatic ovarian serous carcinoma, a metastatic squamous cell carcinoma, a recurrent poorly differentiated skin adnexal carcinoma, and a metastatic thymic carcinoma).

CONCLUSIONS

GATA3 is a useful biomarker for detecting carcinomas of breast or urothelial origin on cytologic specimens. It may detect breast cancers with the triple-negative phenotype. Both cell block and smear preparations can be reliably used for the staining. GATA3-positive immunostaining is occasionally seen in other tumors, which may cause diagnostic confusion.

Venous thromboembolism in metastatic urothelial carcinoma or variant histologies: incidence, associative factors, and effect on survival

Venous thromboembolism (VTE) is common in cancer patients. However, little is known about VTE risk in metastatic urothelial carcinoma or variant histologies (UC/VH). We sought to characterize the incidence, associative factors, including whether various chemotherapy regimens portend different risk, and impact of VTE on survival in metastatic UC/VH patients. Patients diagnosed with metastatic UC/VH from 2000 to 2013 were included in this multicenter retrospective, international study from 29 academic institutions. Cumulative and 6‐month VTE incidence rates were determined. The association of first‐line chemotherapy (divided into six groups) and other baseline characteristics on VTE were analyzed. Each chemotherapy treatment group and statistically significant baseline clinical characteristics were assessed in a multivariate, competing‐risk regression model. VTE patients were matched to non‐VTE patients to determine the impact of VTE on overall survival. In all, 1762 patients were eligible for analysis. There were 144 (8.2%) and 90 (5.1%) events cumulative and within the first 6 months, respectively. VTE rates based on chemotherapy group demonstrated no statistical difference when gemcitabine/cisplatin was used as the comparator. Non‐urotheilal histology (SHR: 2.67; 95% CI: 1.72–4.16, P < 0.001), moderate to severe renal dysfunction (SHR: 2.12; 95% CI: 1.26–3.59, P = 0.005), and cardiovascular disease (CVD) or CVD risk factors (SHR: 2.27; 95% CI: 1.49–3.45, P = 0.001) were associated with increased VTE rates. Overall survival was worse in patients with VTE (median 6.0 m vs. 10.2 m, P < 0.001). Thus, in metastatic UC/VH patients, VTE is common and has a negative impact on survival. We identified multiple associated potential risk factors, although different chemotherapy regimens did not alter risk.

[CCAFU french national guidelines 2016-2018 on upper tract tumors]

INTRODUCTION

The purpose was to propose an update of the french guidelines from the national committee CCAFU on upper tract urothelial carcinomas (UTUC).

METHODS

A systematic Medline search was performed between 2013 and 2016, as regards diagnosis, options of treatment and follow-up of UTUC, to evaluate different references with levels of evidence.

RESULTS

The diagnosis of this rare pathology is based on CT-scan acquisition during excretion and ureteroscopy with histological biopsies. Radical nephroureterectomy (RNU) remains the gold standard for surgical treatment, nevertheless a conservative endoscopic approach can be proposed for low risk lesion: unifocal tumour, possible complete resection and low grade and absence of invasion on CT-scan. Close monitoring with endoscopic follow-up (flexible ureteroscope) in compliant patients is therefore necessary. After RNU, bladder instillation of chemotherapy is recommended to reduced risk of baldder recurrence. The place of systemic therapy (adjuvant and neoadjuvant chemotherapy) remains to define.

CONCLUSION

These updated guidelines will contribute to increase the level of urological care for diagnosis and treatment for UTUC. © 2016 Elsevier Masson SAS. All rights reserved.

Hexavalent chromium induces chromosome instability in human urothelial cells

Numerous metals are well-known human bladder carcinogens. Despite the significant occupational and public health concern of metals and bladder cancer, the carcinogenic mechanisms remain largely unknown. Chromium, in particular, is a metal of concern as incidences of bladder cancer have been found elevated in chromate workers, and there is an increasing concern for patients with metal hip implants. However, the impact of hexavalent chromium (Cr(VI)) on bladder cells has not been studied. We compared chromate toxicity in two bladder cell lines; primary human urothelial cells and hTERT-immortalized human urothelial cells. Cr(VI) induced a concentration- and time-dependent increase in chromosome damage in both cell lines, with the hTERT-immortalized cells exhibiting more chromosome damage than the primary cells. Chronic exposure to Cr(VI) also induced a concentration-dependent increase in aneuploid metaphases in both cell lines which was not observed after a 24h exposure. Aneuploidy induction was higher in the hTERT-immortalized cells. When we correct for uptake, Cr(VI) induces a similar amount of chromosome damage and aneuploidy suggesting that the differences in Cr(VI) sensitivity between the two cells lines were due to differences in uptake. The increase in chromosome instability after chronic chromate treatment suggests this may be a mechanism for chromate-induced bladder cancer, specifically, and may be a mechanism for metal-induced bladder cancer, in general.

Neoadjuvant chemotherapy-related histologic changes in radical cystectomy: assessment accuracy and prediction of response

We evaluated the spectrum of histologic changes associated with neoadjuvant chemotherapy (NAC) and compared them with those resulting from transurethral resection (TUR). Twenty-five patients who received NAC were divided based on both their preoperative clinical/radiographic findings (clinical stage, hydronephrosis, palpable mass) and the cystectomy (RC) findings into NAC respondents (advanced clinical stage and <pT2+pN0), possible NAC respondents (non-advanced clinical stage and <pT2+pN0), and NAC nonrespondents (≥pT2and/or ≥pN1). In addition, 14 patients who received TUR alone and had <pT2+pN0 on RC were included. Presence/absence of the following histologic features was assessed: fibrosis/myofibroblastic reaction, hyalinization in the bladder wall, inflammatory reaction, calcification, foreign-body giant cells, necrosis, sheets of foamy macrophages, and fibrosis/hyalinization/necrosis in the lymph nodes (LNs). Overall, there was a significant histologic overlap between all groups. However, patients who received NAC had a significantly higher likelihood of showing hyalinization and less giant cells and inflammatory reaction than did those who received TUR only. Moreover, the only significantly different histologic features in NAC respondents versus TUR respondents were hyalinization and LN changes, with those 2 features in 25% and 0% of the possible NAC respondents group, respectively. Lastly, there was no significant difference in the possible NAC respondent group in comparison to the TUR-only arm. It appears that TUR and NAC result in overlapping histologic changes. In cases with no/minimal residual disease on RC, it is difficult to attribute the changes to NAC effect only, except if (1) hyalinization of the bladder wall or LN changes are present, or (2) if the preoperative clinical stage was beyond what could be resected by TUR.

Testicular Metastasis of a Upper Urinary Tract High-grade Papillary Urothelial Carcinoma, 2 Years After Nephroureterectomy

Urothelial carcinomas are the fourth most common tumors in men. Upper tract urinary carcinomas (UTUCs) are uncommon and represent only 5–10% of urothelial carcinomas.¹ Metastatic testicular cancers are rare and primary tumor sources are the prostate, lung, and gastrointestinal tract. We report the first case of testicular metastasis 2 years after initial curative surgery for a high-grade UTUC, all other reported cases weren't proceed by curative surgery.³

Prognostic role of ERCC1 protein expression in upper tract urothelial carcinoma following radical nephroureterectomy with curative intent

BACKGROUND

Excision repair cross-complementing 1 (ERCC1) has been associated with outcomes of urothelial carcinoma of the bladder, but was not yet studied in upper tract urothelial carcinoma (UTUC). The aim of this study was to assess the prognostic role of ERCC1 expression in a large international cohort of UTUC patients.

METHODS

Immunohistochemical ERCC1 expression was evaluated in 716 UTUC patients who underwent radical nephroureterectomy with curative intent. ERCC1 was considered positive when the H-score was >1.0. Associations with overall survival and cancer-specific survival were assessed using univariable and multivariable Cox models.

RESULTS

ERCC1 was expressed in 303 tumors (42.3 %) and linked with the presence of tumor necrosis (16.2 vs. 10.4 %, p = 0.023), but not with any other clinical or pathological variable. ERCC1 status did not predict cancer-specific survival and overall survival on both univariable (p = 0.70 and 0.32, respectively) and multivariable analyses (p = 0.48 and 0.33, respectively).

CONCLUSIONS

ERCC1 is expressed in a significant proportion of UTUC and is linked with tumor necrosis, but its expression appears not to be associated with prognosis following radical nephroureterectomy.

Schistosoma haematobium egg-induced bladder urothelial abnormalities dependent on p53 are modulated by host sex

INTRODUCTION AND OBJECTIVE

The bladder urothelium changes dramatically during Schistosoma haematobium infection (urogenital schistosomiasis). These alterations include hyperplasia, ulceration, dysplasia, squamous metaplasia and frank carcinogenesis. Defining the pathways underpinning these urothelial responses will contribute to a deeper understanding of how S. haematobium egg expulsion, hematuria, and bladder cancer develop in humans. The tumor suppressor gene p53 is of particular interest, given its role in many cancers, including bladder cancer generally and schistosomal bladder cancer specifically.

METHODS

Transgenic mice featuring tamoxifen-inducible Cre recombinase activity in cells expressing the urothelial-specific gene uroplakin-3a (Upk3a-GCE mice) were crossed with either TdTomato-floxed-EGFP reporter or p53-floxed mice. Mice were administered tamoxifen or vehicle control to induce excision of floxed genes. TdTomato-EGFP reporter mice were sacrificed and their bladders harvested, sectioned, and imaged by fluorescence microscopy. p53-floxed mice underwent bladder wall injection with S. haematobium eggs or vehicle controls. Three months later, mice were sacrificed and their bladders subjected to histological analysis (H&E staining).

RESULTS

We first confirmed the phenotypic fidelity of Upk3a-GCE mice by crossing them with TdTomato-floxed-EGFP reporter mice and administering tamoxifen to their progeny. As expected, these progeny switched from TdTomato to EGFP expression in their bladder urothelium. Having confirmed the phenotype of Upk3a-GCE mice, we next crossed them to p53-floxed mice. The resulting progeny were given tamoxifen or vehicle control to render them urothelial p53-haploinsufficient or -intact, respectively. Then, we injected S. haematobium eggs or control vehicle into the bladder walls of these mice. Male p53-intact, egg-injected mice exhibited similar histological changes as their p53-haploinsufficient counterparts, including urothelial hyperplasia and ulceration. In contrast, female p53-intact, egg-injected mice featured no urothelial ulceration, whereas their p53-haploinsufficient counterparts often had significant ulceration.

CONCLUSIONS

Urothelial p53 signaling indeed seems to affect urothelial homeostasis during S. haematobium infection, albeit in a sex-specific manner. Ongoing work seeks to determine whether p53 mediates associated alterations in urothelial cell cycle status and frank carcinogenesis in the setting of urogenital schistosomiasis.

Invasive urothelial carcinoma exhibiting basal cell immunohistochemical markers: A variant of urothelial carcinoma associated with aggressive features

We characterize invasive urothelial carcinoma (UC) exhibiting urothelial basal cell immunohistochemical markers. Consecutive invasive UCs were immunostained with CK20 and urothelial basal cell markers, cytokeratin 5 (CK5)/CD44. Immunostaining for CK5 and CD44 was scored as follows: positive for staining of more than 25% thickness of the epithelial nest or epithelium and low for lesser immunoreactivity. Invasive urothelial carcinoma (UC) exhibiting positive CK5/CD44 staining was designated as basal-like UC (BUC). In this study, of 251 invasive UC (pT1 in 57% and pT2-4 in 43%), BUC accounted for 40% of cases (accounting for most pT2-4 UC) and often presented as non-papillary UC without previous history of UC. In addition, BUC exhibited uniform nuclei with lesser degree of atypia than non BUC and decreased or negative cytokeratin 20 reactivity. Nested and microcystic variants of UC immunohistochemically stained as BUCs. Invasive non-BUCs were often papillary with marked cytologic atypia and pleomorphism, and accounted for most pT1 UC. The rates of perivesical invasion, lymph node and distant metastases were higher for BUC than non-BUC. All nine cases with absent/minimal residual in situ UC in 102 radical cystectomy specimens were from invasive non-BUC. BUC is distinguished from non-BUC due to this aggressive behavior, distinct immunohistochemical profile, and predominant non-papillary architecture. Our findings are consistent with recent studies identifying a subtype of muscle-invasive UC with molecular expression of basal cell and luminal cell molecular profiles. Our study further supports categorizing invasive UCs into these subtypes with different biological behaviors, possibly contributing to better therapeutic strategies.

Primary Sarcomatoid Tumor of the Bladder: A Different Entity but the Same Approach?

Bladder cancer remains a frequent cancer worldwide, and most tumors are diagnosed at localized stages. Urothelial carcinoma (UC) accounts for 90% of bladder cancer cases. Sarcomatoid carcinoma (SaC) of the bladder is a rare variant (0.5% of total bladder cancers) characterized by 2 components based on histology; the epithelial and mesenchymal phenotypes, which can be easily differentiated by immunohistochemistry. SaC has similar epidemiologic features to UC but different behavior, aggressiveness, and prognosis. In this review, we summarize the main differences between UC bladder cancers and SaC subtypes. The therapeutic strategies used in SaC today do not differ much from those used for the urothelial variant. However, there is still no standard treatment--the result of a lack of clinical trials for the sarcomatoid variant. Further multicenter comparative studies are needed to devise a better treatment strategy for patients with this rare histologic tumor subtype.