Predicting outcomes in non-muscle invasive (Ta/T1) bladder cancer: the role of molecular grade based on luminal/basal phenotype

Immunophenotypic and molecular changes during progression of papillary urothelial carcinoma

PURPOSE

Urothelial carcinoma has various molecular subtypes, each with different tumor characteristics. Although it is known that molecular changes occur during tumor progression, little is known about the specifics of these changes. In this study, we performed transcriptional analysis to understand the molecular changes during tumor progression.

MATERIALS AND METHODS

Formalin-fixed, paraffin-embedded tumor tissues were obtained from 12 patients with muscle-invasive bladder cancer (MIBC). The invasive and non-invasive papillary areas were identified in papillary urothelial carcinoma specimens. Immunohistochemistry (IHC) and mRNA sequencing were performed for each tumor area.

RESULTS

Patients with CK5/6-negative and CK20-positive non-invasive papillary areas were selected and classified into the IHC switch subgroup (CK5/6-positive and CK20-negative in the invasive area) and the IHC unchanged subgroup (CK5/6-negative and CK20-positive in the invasive area) according to the IHC results of the invasive area. We identified differences in the mRNA expression between the non-invasive papillary and invasive areas of the papillary MIBC tissue samples. In both the non-invasive papillary and invasive areas, the IHC switch subgroup showed basal subtype gene expression, while the IHC unchanged subgroup demonstrated luminal subtype gene expression.

CONCLUSIONS

The non-invasive papillary area showed a gene expression pattern similar to that of the invasive area. Therefore, even if the non-invasive papillary area exhibits a luminal phenotype on IHC, it can have a basal subtype gene expression depending on the invasive area.

Proliferation and immunohistochemistry for p53, CD25 and CK20 in predicting prognosis of non-muscle invasive papillary urothelial carcinomas

Non-muscle invasive papillary urothelial carcinoma is a prevalent disease with a high recurrence tendency. Good prognostic and reproducible biomarkers for tumor recurrence and disease progression are lacking. Currently, WHO grade and tumor stage are essential in risk stratification and treatment decision-making. Here we present the prognostic value of proliferation markers (Ki67, mitotic activity index (MAI) and PPH3) together with p53, CD25 and CK20 immunohistochemistry (IHC). In this population-based retrospective study, 349 primary non-muscle invasive bladder cancers (NMIBC) were available. MAI and PPH3 were calculated manually according to highly standardized previously described methods, Ki-67 by the semi-automated QPRODIT quantification system, p53 and CD25 by the fully automated digital image analysis program Visipharm® and CK20 with the help of the semi-quantitative immunoreactive score (IRS). Survival analyses with log rank test, as well as univariate and multivariate Cox regression analyses were performed for all investigated variables. Age and multifocality were the only significant variables for tumor recurrence. All investigated variables, except gender, were significantly associated with stage progression. In multivariate analysis, MAI was the only prognostic variable for stage progression (p<0.001).

MTHFD2 promotes PD-L1 expression via activation of the JAK/STAT signalling pathway in bladder cancer

Although combination chemotherapy is widely used for bladder cancer (BC) treatment, the recurrence and progression rates remain high. Therefore, novel therapeutic targets are required. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) contributes to tumourigenesis and immune evasion in several cancers; however, its biological function in BC remains unknown. This study aimed to investigate the expression, prognostic value and protumoural function of MTHFD2 in BC and elucidate the mechanism of programmed death-ligand 1 (PD-L1) upregulation by MTHFD2. An analysis using publicly available databases revealed that a high MTHFD2 expression was correlated with clinical features and a poor prognosis in BC. Furthermore, MTHFD2 promoted the growth, migration, invasion and tumourigenicity and decreased the apoptosis of BC cells in vivo and in vitro. The results obtained from databases showed that MTHFD2 expression was correlated with immune infiltration levels, PD-L1 expression, and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. The expression of MTHFD2, PD-L1 and JAK/STAT signalling pathway-related proteins increased after interferon gamma treatment and decreased after MTHFD2 knockdown. Moreover, addition of a JAK/STAT pathway activator partially reduced the effect of MTHFD2 knockdown on BC cells. Collectively, our findings suggest that MTHFD2 promotes the expression of PD-L1 through the JAK/STAT signalling pathway in BC.

Risk Classification of Bladder Cancer by Gene Expression and Molecular Subtype

This study evaluated a panel including the molecular taxonomy subtype and the expression of 27 genes as a diagnostic tool to stratify bladder cancer patients at risk of aggressive behavior, using a well-characterized series of non-muscle invasive bladder cancer (NMIBC) as well as muscle-invasive bladder cancer (MIBC). The study was conducted using the novel NanoString nCounter gene expression analysis. This technology allowed us to identify the molecular subtype and to analyze the gene expression of 27 bladder-cancer-related genes selected through a recent literature search. The differential gene expression was correlated with clinicopathological variables, such as the molecular subtypes (luminal, basal, null/double negative), histological subtype (conventional urothelial carcinoma, or carcinoma with variant histology), clinical subtype (NMIBC and MIBC), tumor stage category (Ta, T1, and T2–4), tumor grade, PD-L1 expression (high vs. low expression), and clinical risk categories (low, intermediate, high and very high). The multivariate analysis of the 19 genes significant for cancer-specific survival in our cohort study series identified TP53 (p = 0.0001), CCND1 (p = 0.0001), MKI67 (p < 0.0001), and molecular subtype (p = 0.005) as independent predictors. A scoring system based on the molecular subtype and the gene expression signature of TP53, CCND1, or MKI67 was used for risk assessment. A score ranging from 0 (best prognosis) to 7 (worst prognosis) was obtained and used to stratify our patients into two (low [score 0–2] vs. high [score 3–7], model A) or three (low [score 0–2] vs. intermediate [score 3–4] vs. high [score 5–7], model B) risk categories with different survival characteristics. Mean cancer-specific survival was longer (122 + 2.7 months) in low-risk than intermediate-risk (79.4 + 9.4 months) or high-risk (6.2 + 0.9 months) categories (p < 0.0001; model A); and was longer (122 + 2.7 months) in low-risk than high-risk (58 + 8.3 months) (p < 0.0001; model B). In conclusion, the molecular risk assessment model, as reported here, might be used better to select the appropriate management for patients with bladder cancer.

Progression-associated molecular changes in basal/squamous and sarcomatoid bladder carcinogenesis

The aggressive basal/squamous (Ba/Sq) bladder cancer (BLCA) subtype is often diagnosed at the muscle-invasive stage and can progress to the sarcomatoid variant. Identification of molecular changes occurring during progression from non-muscle-invasive BLCA (NMIBC) to Ba/Sq muscle-invasive BLCA (MIBC) is thus challenging in human disease. We used the N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) mouse model of Ba/Sq MIBC to study longitudinally the molecular changes leading to the Ba/Sq phenotype and to the sarcomatoid variant using IHC and microdissection followed by RNA-seq at all stages of progression. A shift to the Ba/Sq phenotype started in early progression stages. Pathway analysis of gene clusters with coordinated expression changes revealed Shh signaling loss and a shift from fatty acid metabolism to glycolysis. An upregulated cluster, appearing early in carcinogenesis, showed relevance to human disease, identifying NMIBC patients at risk of progression. Similar to the human counterpart, sarcomatoid BBN tumors displayed a Ba/Sq phenotype and epithelial-mesenchymal transition (EMT) features. An EGFR/FGFR1 signaling switch occurred with sarcomatoid dedifferentiation and correlated with EMT. BLCA cell lines with high EMT were the most sensitive to FGFR1 knockout and resistant to EGFR knockout. Taken together, these findings provide insights into the underlying biology of Ba/Sq BLCA progression and sarcomatoid dedifferentiation with potential clinical implications. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Influence of luminal and basal subtype in prognosis of high-grade non muscle invasive urothelial carcinoma

BACKGROUND

Recent studies have shown that the classification of high-grade urothelial carcinoma non-muscle invasive (HGBCNMI) based on molecular subtypes might be a valuable strategy to identify patients with a worse clinical prognosis.

OBJECTIVE

Determine the effect of the luminal and basal molecular subtype determined by immunistochemical on prognosis in patients with HGBC in Mexican population.

METHODS

Phenotypes were evaluated by immunohistochemical staining of luminal (GATA3, FOXA1) and basal (CK5/6, CK14) markers in paraffin-embedded tissue samples from 45 patients with a diagnosis of HGBCNMI treated at Instituto Nacional de Cancerología-México (INCan) between 2009 and 2019. The association with prognosis was evaluated using Kaplan-Meier curves and multivariable-adjusted Cox models.

RESULTS

HGBCNMI patients showed mean age of 58.77 years (SD: ±12.08 years). We identified expression of the luminal molecular subtype in 35 cases (77.78 %), and 10 cases (22.22 %) with "combined" expression of the molecular subtype (basal and luminal expression). The combined phenotype was statistically more frequent in metastatic cases (p-value = 0.028). In Kaplan-Meier curves, combined expression of luminal and basal molecular markers was associated with disease progression (p-value = 0.002, log-rank test). Cox regression models confirmed this association, which was not influenced by age (p-value = 0.007) or gender (p-value = 0.007). No association of phenotypes with overall survival (p-value = 0.860) or relapse (p-value = 0.5) was observed.

CONCLUSION

The combined expression of immunohistochemical markers of the luminal and basal subtype might be considered as predictor for disease progression in patients with HGBCNMI in Mexican population.

Update on Flat and Papillary Urothelial Lesions: Genitourinary Pathology Society Consensus Recommendations

The reporting recommendations on "flat and papillary urothelial neoplasia," published in 2 position articles by the Genitourinary Pathology Society in July 2021, was a collective contribution of 38 multidisciplinary experts aiming to clarify nomenclature, classification of flat and papillary urothelial neoplasia and controversial issues. In this review, we discuss some of these recommendations including nomenclature, practical approaches, and their importance for clinical practice.

Non-muscle invasive bladder cancer biomarkers beyond morphology

Non-muscle invasive bladder cancer (NMIBC) still represents a challenge in decision-making and clinical management since prognostic and predictive biomarkers of response to treatment are still under investigation. In addition to the risk factors defined by EORTC guidelines, histological features have also been considered key variables able to impact on recurrence and progression in bladder cancer. Conversely, the role of genomic rearrangements or expression of specific proteins at tissue level need further assessment in NMIBC. As with muscle-invasive cancer, NMIBC is a heterogeneous disease, characterized by genomic instability, varying rates of mutation and a wide range of protein tissue expression. In this Review, we summarized the recent evidence on prognostic and predictive tissue biomarkers in NMIBC, beyond morphological parameters, outlining how they could affect tumor biology and consequently its behavior during clinical care. Our aim was to facilitate clinical evaluation of promising biomarkers that may be employed to better stratify patients. We described the most common molecular events and immunohistochemical protein expressions linked to recurrence and progression. Moreover, we discussed the link between available treatments and molecular drivers that could be predictive of clinical response. In conclusion, we foster further investigations with particular focus on immunohistochemical evaluation of tissue biomarkers, a promising and cost-effective tool for daily practice.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 2: Subtypes and Divergent Differentiation

Following several attempts to achieve a molecular stratification of bladder cancer (BC) over the last decade, a "consensus" classification has been recently developed to provide a common base for the molecular classification of bladder cancer (BC), encompassing a six-cluster scheme with distinct prognostic and predictive characteristics. In order to implement molecular subtyping (MS) as a risk stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The second part of this review deals with the pathological and clinical features of the molecular clusters, both in conventional and divergent urothelial carcinoma, with a focus on the role of IHC-based subtyping.

Are We Ready to Implement Molecular Subtyping of Bladder Cancer in Clinical Practice? Part 1: General Issues and Marker Expression

Bladder cancer (BC) is a heterogeneous disease with highly variable clinical and pathological features, and resulting in different outcomes. Such heterogeneity ensues from distinct pathogenetic mechanisms and may consistently affect treatment responses in single patients. Thus, over the last few years, several groups have developed molecular classification schemes for BC, mainly based on their mRNA expression profiles. A “consensus” classification has recently been proposed to combine the published systems, agreeing on a six-cluster scheme with distinct prognostic and predictive features. In order to implement molecular subtyping as a risk-stratification tool in routine practice, immunohistochemistry (IHC) has been explored as a readily accessible, relatively inexpensive, standardized surrogate method, achieving promising results in different clinical settings. The first part of this review deals with the steps resulting in the development of a molecular subtyping of BC, its prognostic and predictive implications, and the main features of immunohistochemical markers used as surrogates to stratify BC into pre-defined molecular clusters.

Intratumoral Switch of Molecular Phenotype and Overall Survival in Muscle Invasive Bladder Cancer

In recent years, immunohistochemical protein expression was studied as a surrogate to the molecular classification of bladder cancer, although no tissue biomarkers are available for clinical use to predict survival or the response to neoadjuvant chemotherapy (CT) in UC, as the literature produced conflicting results. This retrospective study included TURB specimens harboring foci of HG pT2 muscle-invasive bladder carcinoma (MIBC) from 251 patients who subsequently underwent radical cystectomy. We performed immunohistochemical analysis on tumor samples, for relevant gene-expression-based markers for basal type (CD44, CK5/6) and luminal type (CK20 and pPARγ). Piescore, investigated in both non-muscle-invasive (NMI) and muscle-invasive (MI) components of the tumor, divided basal and luminal UC-types when at least three of the four markers were consistent with a specific phenotype, mixed types if one/two luminal and basal markers were present simultaneously, and neu-like types when all four markers investigated were negative. Eighteen selected cases were also investigated with RT-PCR to validate, and to increase the specificity of, the immunohistochemical results. We observe an immunophenotypical difference in the NMI and MI components in 96/251 UC patients (38.25%): half of tumors (44/96 cases) have a transition to basal, 36.46% (35/96 cases) to neu-like, 12.5% (12/96 cases) to mixed, and 5.2% (5/96 cases) to luminal phenotypes. Mixed tumors in the NMI component are more likely to change phenotype than other groups, particularly compared with basal tumors, which demonstrate greater stability (only 8/96 cases, p < 0.00001). The transition of luminal tumors to basal display a better OS compared with the transition toward neu-like tumors (p = 0.027). Overall, the phenotypical switch does not affect lymphovascular invasion, pT, DFS, or OS compared with non-switched cases. In the MI component, the presence of CD44 expression, irrespective of score-related phenotype, shows a protective effect in papillary-type UC (OS p = 0.008, HR 0.453, PFS p = 0.07, HR 0.599), and in UC naïve for CT (p = 0.0479). Piescore immunophenotyping reveals an intratumoral phenotypical transition between the NMI and MI components of the same tumor. The molecular change is a common event in the mixed and luminal categories, but not in basal tumors, which show better phenotypical stability. This phenomenon could partially explain the sensitivity of a subset of luminal UC to chemotherapy: good responders could be “non-real” luminal UC, which acquire nasal markers, such as CD44.

Immunohistochemistry subtyping of urothelial carcinoma is feasible in the daily practice

The preferred treatment of choice in muscle-invasive bladder cancer (MIBC) is usually transurethral resection followed by cystectomy, with neoadjuvant chemotherapy being a second option. As the treatment is associated with relevant side effects, a great effort is being made to improve the selection of patients, with molecular subtyping being one of the main strategies. Our aim was to develop an immunohistochemical algorithm for subtyping MIBCs. After a literature review, we have developed a simple algorithm to subtype MIBCs based on their morphology and three common antibodies: GATA3, CK5/6, and p16. We applied it to 113 muscle-invasive carcinomas. The positivity threshold for GATA3 and CK5/6 was 20% with at least moderate intensity, while p16 was 70% with moderate to intense nuclear and cytoplasmic staining. Cases GATA3 + CK5/6 - were considered luminal, while cases GATA3 - CK5/6 + were classified as nonluminal/basal squamous. Luminal p16 + cases were labeled as genomically unstable and luminal p16 - as Uro-like. Cases GATA3 + CK5/6 + with a predominantly basal pattern were labeled luminal, while diffuse cases were labeled nonluminal/basal squamous. All GATA3-CK5/6 - cases were considered nonluminal and were divided into mesenchymal-like or neuroendocrine, depending on the morphology. We were able to classify the 113 cases as: 82 (72.57%) were luminal, being 47 Uro-like (41.59%) and 35 (30.97%) genomically unstable; 31 (27.43%) were nonluminal, being 24 basal/squamous (21.24%), two (1.76%) mesenchymal-like, and five (4.42%) neuroendocrine like. We have achieved a feasible and cost-effective algorithm to subtype MIBCs from morphological features and the use of three common antibodies. Further studies in external cohorts are necessary to validate these results.

Uroplakin II as a single marker for luminal versus basal molecular subtypes in muscle invasive urothelial carcinoma

Bladder cancer is a heterogeneous disease classified into two broad molecular subtype categories, basal and luminal, with critical treatment and prognostic implications. Recent studies have shown the utility of immunohistochemistry in predicting bladder cancer molecular subtypes, with a two-marker approach using GATA3 and CK5/6 showing over 80% reliability. In the current study, we calculated the accuracy of uroplakin II (UPII), a marker of urothelial differentiation, with different scores (0: <1%, 1+: 1-10%, 2+: 10-50%, 3+: >50%) to predict RNA-based luminal versus basal subtypes in a cohort of muscle-invasive bladder cancer-received neoadjuvant chemotherapy followed by radical cystectomy. The 1% cutoff of the UPII stain predicts the luminal subtype with the sensitivity and specificity of 95% and 56%, respectively. With a UPII cutoff of 10%, the sensitivity and specificity were 93% and 81%, respectively, and with a UPII cutoff of 50%, the sensitivity and specificity were 91% and 96%, respectively. The prediction performance of UPII was better than either GATA3 or CK5/6. There was no significant difference in prognoses between UPII 0-2+ and UPII 3+ patients in this cohort. The current study shows that evaluating the staining proportion score of UPII can accurately predict basal and luminal subtypes of muscle-invasive bladder cancer.

Profiling the Biological Characteristics and Transitions through Upper Tract Tumor Origin, Bladder Recurrence, and Muscle-Invasive Bladder Progression in Upper Tract Urothelial Carcinoma

To evaluate biological characteristics and transitions of upper tract urothelial carcinoma (UTUC) through metachronous bladder tumors after radical nephroureterectomy (RNU), we conducted immunohistochemical (IHC) staining of tumor specimens of UTUC tumor origin, non-muscle-invasive bladder cancer (NMIBC) and MIBC progressed after intravesical recurrence (IVR), and bladder primary MIBC. Fibroblast growth factor receptor 3 (FGFR3), p53, cytokeratin 5/6 (CK5/6), and CK20 were stained to examine expression rates. After expression assessment with heatmap clustering, the overexpression of four biomarkers from UTUC origin to metachronous MIBC progression was analyzed with clinicopathological variables. We found that high CK20 and low CK5/6 expression were both observed in UTUC tumor origin and subsequent NMIBC after RNU. By investigating molecular expression in the IVR specimen, we observed that low pT stage bladder recurrence occupied the majority of CK20 high CK5/6 low expression, but would change to CK20 low CK5/6 high expression as it progressed to MIBC. UTUC metachronous MIBC has different characteristics compared with bladder primary MIBC, which comprises favorable biological features such as high FGFR3 expression, and follows favorable prognosis compared to those without FGFR3 expression. The present study demonstrated that the biological characteristics of UTUC tumor origin shifts from luminal to basal-like features with progression to MIBC, but FGFR3 expression taken over from UTUC origin may comprise a favorable entity compared to primary MIBC.

Molecular classification of patients with NMIBC predicts the efficacy of intravesical chemotherapy with pirarubicin, pharmorubicin and gemcitabine-immunohistochemistry-based classification

Objective

To investigate the relationships between non-muscle invasive bladder cancer molecular subtypes and predict the efficacy of intravesical chemotherapy with pirarubicin, pharmorubicin and gemcitabine.

Methods

A total of 160 patients with T1 stage non-muscle invasive bladder cancer were enrolled in this study. Fifty-three patients underwent anthracycline (Pirarubicin and Pharmorubicin) therapy and 107 patients accepted gemcitabine therapy. Uroplakin II and CK20 were categorized as immunohistochemistry (IHC) markers for luminal subtype, whereas CK5/6 and CD44 were categorized as immunohistochemistry markers for basal subtype. The cluster results with immunohistochemical score indicated that non-muscle invasive bladder cancer can be subgrouped into three major classes.

Results

Class 2 showed the luminal-like characteristics, whereas class 3 showed the basal-like characteristics. Class 1 showed no high expression of luminal or basal-associated immunohistochemistry markers. The molecular subtype is an independent risk factor for recurrence-free survival (P = 0.030) and progression-free survival (P = 0.006) in patients with T1 stage non-muscle invasive bladder cancer. In class 1 and class 2 (luminal-like) subtypes, gemcitabine and anthracycline show no difference in recurrence-free survival and progression-free survival. Gemcitabine was associated with reduced recurrence compared with anthracycline (P = 0.039) in class 3 (basal-like) subtypes and show no difference in decreasing progression.

Conclusions

The molecular classification based on immunohistochemical results is an independent risk factor for the prognosis of non-muscle invasive bladder cancer with T1 stage. Different therapeutic methods should be selected according to different molecular subtypes.

Subcategorization of T1 Bladder Cancer on Biopsy and Transurethral Resection Specimens for Predicting Progression

CONTEXT.—

Despite continued surveillance and intravesical therapy, a significant subset of patients with lamina propria-invasive bladder cancer (T1) will progress to muscle-invasive disease or metastases.

OBJECTIVE.—

To analyze the value of pathologic subcategorization of T1 disease in predicting progression.

DESIGN.—

Six substaging methods were applied to a retrospective cohort of 73 patients, with pT1 urothelial carcinoma diagnosed on biopsy/transurethral resection. Additionally, the immunohistochemistry for GATA3 and cytokeratin 5/6 (CK5/6) was performed to study the prognostic value of stratifying T1 cancers into luminal or basal phenotypes.

RESULTS.—

On follow-up (mean, 46 months), 21 (29%) experienced at least 1 recurrence without progression, and 16 (22%) had progression to muscle-invasive disease and/or distant metastasis. No differences were noted between progressors and nonprogressors with regard to sex, age, treatment status, medical history, tumor grade, and presence of carcinoma in situ. Substaging using depth of invasion (cutoff ≥1.4 mm), largest invasive focus (≥3.6 mm), aggregate linear length of invasion (≥8.9 mm), and number of invasive foci (≥3 foci) correlated significantly with progression and reduced progression-free survival, whereas invasion into muscularis mucosa or vascular plexus, or focal versus extensive invasion (focal when ≤2 foci, each <1 mm) failed. Patients with luminal tumors had higher incidence of progression than those with nonluminal tumors (27% versus 11%), although the difference was statistically insignificant (P = .14).

CONCLUSIONS.—

Substaging of T1 bladder cancers should be attempted in pathology reports. Quantifying the number of invasive foci (≥3) and/or measuring the largest contiguous focus of invasive carcinoma (≥3.6 mm) are practical tools for prognostic substaging of T1 cancers.

CALD1 promotes the expression of PD-L1 in bladder cancer via the JAK/STAT signaling pathway

Background

Bladder cancer (BC) is a common malignant neoplasm with a high rate of recurrence and progression, despite optimal treatment. There is a pressing need to identify new effective biomarkers for the targeted treatment of BC.

Methods

The key gene CALD1 was screened via weighed gene co-expression network analysis (WGCNA) from encoding protein genes of BC. Clinical and prognostic significance was explored in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Cell Counting Kit-8 (CCK-8), flow cytometry, transwell chamber experiment and nude mouse xenograft assay were performed to test cell growth, apoptosis, migration, invasion and tumorigenesis capacities. Immune correlation was analyzed in The Tumor Immune Estimation Resource (TIMER) database. Relevant signaling pathways were explored using gene set enrichment analysis (GSEA).

Results

Increased expression of CALD1 was significantly correlated with histological grade, clinical stage, T stage, and lymphatic metastasis. Kaplan-Meier survival curves showed that high CALD1 expression was associated with poor overall survival (OS) and disease-free survival (DFS) in TCGA database, and with poor OS in the four GEO databases. CALD1 promotes growth, migration, invasion, and cell cycle of tumor cell, and inhibits tumor cell apoptosis in vitro and in vivo. CADL1 expression was positively correlated with increased CD274 levels (r=0.357, P=9.71e−14). JAK/STAT signaling pathway was significantly enriched in the high CALD1 expression group. CALD1-mediated PD-L1 overexpression (OE) was via the activation of the JAK/STAT signaling pathway; this effect was blocked by the specific JAK inhibitor Ruxolitinib.

Conclusions

CALD1 is a potential molecular marker associated with prognosis. It promotes the malignant progression of BC and upregulates the PD-L1 expression via the JAK/STAT signaling pathway.

Molecular Classification of Bladder Urothelial Carcinoma Using NanoString-Based Gene Expression Analysis

Simple Summary

Our study aimed to apply a quantitative method based on mRNA counting as nCounter (NanoString Technologies, Inc). This method can obtain precise and accurate measures of RNA expression compared to RT-PCR, and which might represent an alternative to the NGS-genomic/transcriptomic profiling frequently used to generate molecular data in bladder cancer and provide clinically meaningful datasets for the molecular classification of bladder cancer. The current study generated a four-gene classifier, incorporating GATA3 and KRT20 (typically related to luminal molecular subtype) and KRT5 and KRT14 (typically related to basal molecular subtype). This methodology allowed us to explore differences in clinicopathologic parameters and potential sensitivities to ICI immunotherapy in a cohort series of 91 urothelial carcinomas of the bladder.

Abstract

Molecular classification of bladder carcinoma is a relevant topic in modern bladder cancer oncology due to its potential to improve oncological outcomes. The available molecular classifications are generally based on transcriptomic profiles, generating highly diverse categories with limited correlation. Implementation of molecular classification in practice is typically limited due to the high complexity of the required technology, the elevated costs, and the limited availability of this technology worldwide. We have conducted a gene expression analysis using a four-gene panel related to luminal and basal subtypes in a series of 91 bladder cancer cases. NanoString-based gene expression analysis using typically luminal (GATA3+/KRT20+) and basal markers (KRT14+/KRT5+/GATA3low/-/KRT20low/-) classified urothelial bladder carcinoma samples as luminal, basal, and a third category (KRT14-/KRT5-/GATA3-/KRT20-), null/double negative (non-luminal/non-basal). These three categories were meaningful in terms of overall cancer-specific survival (p < 0.0001) or when classified as conventional urothelial carcinoma and variant histology urothelial carcinoma (p < 0.0001), NMIBC vs. MIBC (p < 0.001), or by AJCC stage category Ta (p = 0.0012) and T1 (p < 0.0001) but did not reach significance in T2-T4 (p = 0.563). PD-L1 expression (low vs. high) was also different according to molecular subtype, with high PD-L1 expression mostly seen in basal and null subtypes and carcinomas with variant histology (p = 0.002). Additionally, the luminal subtype was enriched in NMIBC with favorable cancer-specific survival (p < 0.0001). In contrast, basal and null subtypes resulted in aggressive MIBC tumors with shorter cancer-specific survival (p < 0.0001), some of which presented variant histology. In conclusion, a comprehensive evaluation of a gene classifier related to molecular taxonomy using NanoString technology is feasible. Therefore, it might represent an accessible and affordable tool in this rapidly expanding area of precision genomics.

Diagnostic and prognostic implications of a three-antibody molecular subtyping algorithm for non-muscle invasive bladder cancer

Intrinsic molecular subtypes may explain marked variation between bladder cancer patients in prognosis and response to therapy. Complex testing algorithms and little attention to more prevalent, early‐stage (non‐muscle invasive) bladder cancers (NMIBCs) have hindered implementation of subtyping in clinical practice. Here, using a three‐antibody immunohistochemistry (IHC) algorithm, we identify the diagnostic and prognostic associations of well‐validated proteomic features of basal and luminal subtypes in NMIBC. By IHC, we divided 481 NMIBCs into basal (GATA3⁻/KRT5⁺) and luminal (GATA3⁺/KRT5 variable) subtypes. We further divided the luminal subtype into URO (p16 low), URO‐KRT5⁺ (KRT5⁺), and genomically unstable (GU) (p16 high) subtypes. Expression thresholds were confirmed using unsupervised hierarchical clustering. Subtypes were correlated with pathology and outcomes. All NMIBC cases clustered into the basal/squamous (basal) or one of the three luminal (URO, URO‐KRT5⁺, and GU) subtypes. Although uncommon in this NMIBC cohort, basal tumors (3%, n = 16) had dramatically higher grade (100%, n = 16, odds ratio [OR] = 13, relative risk = 3.25) and stage, and rapid progression to muscle invasion (median progression‐free survival = 35.4 months, p = 0.0001). URO, the most common subtype (46%, n = 220), showed rapid recurrence (median recurrence‐free survival [RFS] = 11.5 months, p = 0.039) compared to its GU counterpart (29%, n = 137, median RFS = 16.9 months), even in patients who received intravesical immunotherapy (p = 0.049). URO‐KRT5⁺ tumors (22%, n = 108) were typically low grade (66%, n = 71, OR = 3.7) and recurred slowly (median RFS = 38.7 months). Therefore, a simple immunohistochemical algorithm can identify clinically relevant molecular subtypes of NMIBC. In routine clinical practice, this three‐antibody algorithm may help clarify diagnostic dilemmas and optimize surveillance and treatment strategies for patients.

Association of current molecular subtypes in urothelial carcinoma with patterns of muscularis propria invasion

Urothelial carcinoma is subdivided into luminal (L), basal (B), and p53-wild-type (WT) molecular subtypes, with basal and p53-WT groups showing more aggressive course and poor treatment response, respectively. The literature on molecular subtypes of UC includes a mixture of different stages. We investigated the molecular profile and outcome of pure cohort of muscle invasive bladder carcinoma (MIBC) considering two distinct patterns of muscularis propria (MP) invasion. Forty-three cystectomies harboring stage pT2 were retrospectively identified in 18 years. MP invasion was subclassified into patterns 1 (tumor encasing intact detrusor muscle bundles) and 2 (tumor dissecting/replacing detrusor muscle). Using IHC, B/L phenotypes, p53, and Ki67 were assessed, and survival data was collected. Pattern 1 invasion was noted in 16 (37%) and pattern 2 in 27 (63%), with mean age of pattern 1 being 10 years younger. B/L phenotypes were successfully determined in 83.7%; 48.8% and 34.8% revealed L and B phenotypes, respectively (indeterminate phenotype in 16.4%). Pattern 1 was associated with L phenotype (GATA3 and HER-2 expressions: p = 0.02 & p = 0.04, respectively). Ki67 ≥ 5/10HPF was noted in pattern 2 and B phenotype (p = 0.03). B phenotype showed association with p53-WT (p = 0.007). In median follow-up of 60.7 months, 63.6% of pattern 1 cases were alive without disease compared to 32% of pattern 2 (not significant). A panel of CK20 and GATA3 for luminal and CK5/6 and CK14 for basal subtypes can provide reliable molecular classification in UC. Also, morphology of MIBC can predict the molecular phenotype and the behavior of the UC.

The Genitourinary Pathology Society Update on Classification and Grading of Flat and Papillary Urothelial Neoplasia With New Reporting Recommendations and Approach to Lesions With Mixed and Early Patterns of Neoplasia

The Genitourinary Pathology Society (GUPS) undertook a critical review of the recent advances in bladder neoplasia with a focus on issues relevant to the practicing surgical pathologist for the understanding and effective reporting of bladder cancer, emphasizing particularly on the newly accumulated evidence post-2016 World Health Organization (WHO) classification. The work is presented in 2 manuscripts. Here, in the first, we revisit the nomenclature and classification system used for grading flat and papillary urothelial lesions centering on clinical relevance, and on dilemmas related to application in routine reporting. As patients of noninvasive bladder cancer frequently undergo cystoscopy and biopsy in their typically prolonged clinical course and for surveillance of disease, we discuss morphologies presented in these scenarios which may not have readily applicable diagnostic terms in the WHO classification. The topic of inverted patterns in urothelial neoplasia, particularly when prominent or exclusive, and beyond inverted papilloma has not been addressed formally in the WHO classification. Herein we provide a through review and suggest guidelines for when and how to report such lesions. In promulgating these GUPS recommendations, we aim to provide clarity on the clinical application of these not so uncommon diagnostically challenging situations encountered in routine practice, while also importantly advocating consistent terminology which would inform future work.

Molecular pathology of urothelial carcinoma

The current personalized oncology era has witnessed significant efforts to integrate clinical, pathological, and molecular classifications. The growing need for molecular biomarkers to feed personalized oncology, together with the unprecedented wealth of knowledge on the molecular basis of bladder cancer, has led to a novel approach to this disease, incorporating molecularly generated data in clinical practice for locally advanced or metastatic disease. Translational research allows a better understanding of the early events in the development of urothelial carcinoma in the urinary bladder. Thus, mutations in the KMT2D and KDM6A chromatin-modifying genes confer competitive advantages that drive cells to colonize larger regions of the urothelium. Additional mutations in TP53, PIK3CA, FGFR3, or RB1 genes then trigger the process of malignant transformation in the urothelium. In the current review, we provide an overview of what could be the expected transition from the morphology-based classification to a combined, molecularly enriched reporting of clinically meaningful parameters aiming to promote personalized oncology of urothelial carcinoma.

Impact of immunohistochemistry-based molecular subtype on predicting chemotherapy response and survival in patients with T1 stage bladder cancer after bladder-preserving treatment

OBJECTIVE

To explore the immunohistochemistry-based molecular subtypes of bladder cancer, and their impact on the prognosis and the chemotherapy response between gemcitabine plus cisplatin intra-arterial chemotherapy and epirubicin-inducted intravesical chemotherapy, in patients with T1 stage bladder cancer after bladder-preserving treatment.

METHODS

One hundred and seventy-six patients with T1 stage bladder cancer were selected for this study. Thirty-three patients underwent radical cystectomy, 43 received gemcitabine plus cisplatin intra-arterial chemotherapy and 100 received intravesical chemotherapy. The markers labeled with luminal (GATA3, Uroplakin II, CK20) and basal (CK5/6, CK14, CD44) phenotypes were chosen as candidate markers.

RESULTS

One hundred and seventy-six patients were divided into 76 patients as basal/squamous (BASQ), 45 as the luminal A and 55 as the luminal B. Compared with the luminal B and BASQ tumors, the luminal A tumors showed a trend for better recurrence-free survival (P = 0.105) and progression-free survival (P = 0.093). The combination of CK20 and GATA3 was practical to identify the molecular phenotypes with total 84.9% accuracy and significantly associated with recurrence-free survival (P = 0.025) and progression-free survival (P = 0.004). The patient with BASQ tumors who received intravesical chemotherapy showed a trend for worse progression-free survival than the patient who received gemcitabine plus cisplatin intra-arterial chemotherapy or radical cystectomy. Furthermore, the patients with BASQ tumors experienced a significant improvement in progression-free survival after gemcitabine plus cisplatin intra-arterial chemotherapy compared with the patients who received intravesical chemotherapy (P = 0.011).

CONCLUSIONS

The immunohistochemistry-based molecular subtypes could predict the patient's prognosis and clinically different chemotherapeutic survival outcomes in patients with T1 stage bladder cancer after bladder-preserving treatment.

Intratumoral heterogeneity of surrogate molecular subtypes in urothelial carcinoma in situ of the urinary bladder: implications for prognostic stratification of high-risk non-muscle-invasive bladder cancer

Reliable factors predicting the disease course of non-muscle-invasive bladder cancer (NMIBC) with carcinoma in situ (CIS) are unavailable. Molecular subtypes have potential for prognostic stratification of muscle-invasive bladder cancer, while their value for CIS patients is unknown. Here, the prognostic impact of both clinico-pathological parameters, including CIS focality, and immunohistochemistry-based surrogate subtypes was analyzed in a cohort of high-risk NMIBC patients with CIS. In 128 high-risk NMIBC patients with CIS, luminal (KRT20, GATA3, ERBB2) and basal (KRT5/6, KRT14) surrogate markers as well as p53 were analyzed in 213–231 biopsies. To study inter-lesional heterogeneity of CIS, marker expression in independent CIS biopsies from different bladder localizations was analyzed. Clinico-pathological parameters and surrogate subtypes were correlated with recurrence-free (RFS), progression-free (PFS), cancer-specific (CSS), and overall survival (OS). Forty-six and 30% of CIS patients exhibited a luminal-like (KRT20-positive, KRT5/6-negative) and a null phenotype (KRT20-negative, KRT5/6-negative), respectively. A basal-like subtype (KRT20-negative, KRT5/6-positive) was not observed. A significant degree of inter-lesional CIS heterogeneity was noted, reflected by 23% of patients showing a mixed subtype. Neither CIS surrogate subtype nor CIS focality was associated with patient outcome. Patient age and smoking status were the only potentially independent prognostic factors predicting RFS, PFS, OS, and PFS, respectively. In conclusion, further clarification of heterogeneity of surrogate subtypes in HR NMIBC and their prognostic value is of importance with regard to potential implementation of molecular subtyping into clinical routine. The potential prognostic usefulness of patient age and smoking status for high-risk NMIBC patients with CIS needs further validation.

A narrative review of individualized treatments of genitourinary tumors: is the future brighter with molecular evaluations?

Few molecular prognostic and predictive biomarkers have been identified so far in genitourinary tumors. We started from a literature search to explore the status of the art of molecular pathology tests as diagnostic, prognostic, predictive biomarkers in genitourinary cancers. Next generation sequencing approaches now provide mind-changing information in the fields of kidney cancer diagnosis, predictive oncology of urothelial cancer, understanding the causes of testicular and penile cancer, and the comprehension of the drivers of prostate cancer progression beyond androgen regulation. The classification of kidney cancer will be based soon on molecular changes. The causes of non-HPV related penile cancer are largely unknown. The emerging high incidence of testicular cancer could be explained only on the basis of molecular changes. The response to novel therapeutic agents in prostatic and urothelial cancer will require thorough molecular tumor characterization. The hereditary risk of patients with early onset prostate cancer and their potential treatment with targeted therapy requires germline and somatic genetic assays. The implementation of effective biomarkers for the response to immune check-point inhibitors in genitourinary cancer is based on the assessment of inflammatory expression profiles and the tumor mutational burden. This review deals with the current tests and provides a tentative foresee of the future molecular biomarkers of genitourinary cancer.

Immune Checkpoint Inhibitors for the Treatment of Bladder Cancer

A number of immune checkpoint inhibitors (ICIs) have been approved as first-line therapy in case of cisplatin-ineligible patients or as second-line therapy for patients with metastatic urothelial carcinoma (mUC) of the bladder. About 30% of patients with mUC will respond to ICIs immunotherapy. Programmed death-ligand 1 (PD-L1) expression detected by immunohistochemistry seems to predict response to immune checkpoint inhibitors in patients with mUC as supported by the objective response rate (ORR) and overall survival (OS) associated with the response observed in most clinical trials. Pembrolizumab, an anti-PD-1 antibody, demonstrated better OS respective to chemotherapy in a randomized phase 3 study for second-line treatment of mUC. Nivolumab, a PD-1 antibody, also demonstrated an OS benefit when compared to controls. Atezolizumab, Durvalumab, and Avelumab antibodies targeting PD-L1 have also received approval as second-line treatments for mUC with durable response for more than 1 year in selected patients. Atezolizumab and Pembrolizumab also received approval for first-line treatment of patients that are ineligible for cisplatin. A focus on the utility of ICIs in the adjuvant or neoadjuvant setting, or as combination with chemotherapy, is the basis of some ongoing trials. The identification of a clinically useful biomarker, single or in association, to determine the optimal ICIs treatment for patients with mUC is very much needed as emphasized by the current literature. In this review, we examined relevant clinical trial results with ICIs in patients with mUC alone or as part of drug combinations; emphasis is also placed on the adjuvant and neoadjuvant setting. The current landscape of selected biomarkers of response to ICIs including anti-PD-L1 immunohistochemistry is also briefly reviewed.

Stratification of urinary bladder carcinoma based on immunohistochemical expression of CK5, CK14 and CK20

Molecular subtyping of urothelial carcinoma (UC) is similar to that of breast cancer and is based on the developmental biology approach. The aim of the present study is to assess the prognostic impact of CK5, CK14, and CK20 expression in urinary bladder cancer (UBC) with the potential to stratify them into different subtypes. The current study examined the immunohistochemical expression of CK5, CK14, and CK20 in 90 specimens of UBC. CK5 was expressed in 81.1% of the cases and was significantly associated with old age, muscle invasion, presence of bilharziasis, and tendency for poor overall survival. CK20 was expressed in 47.8% of the cases and was associated with nonmuscle invasion and pure UC while 50% of the cases expressed CK14 that were associated with muscle invasion and perineural invasion. Most squamous cell carcinoma and those associated with bilharziasis were belonged to Ck5+/CK20- subgroup while pure UC and those lacked bilharziasis were located in the Ck5+/CK20+ subgroup. The basal group (Ck5+/CK14+/CK20-) showed high proliferative features compared to the intermediate group (Ck5+/CK14-/CK20-). Generally, presence of CK5 is associated with adverse features especially in the group lacking CK20; however, basal and intermediate subgroups share CK5 expression but they show different proliferative capacities, so their distinction by CK14 is helpful.

Stage T1 bladder cancer: diagnostic criteria and pitfalls

Accurate pathological staging is crucial for patient management. Patients with T1 bladder cancer are at risk of recurrence, progression, and death of cancer. Recognition of early invasion (stage T1 disease) in urothelial carcinoma remains one of the most challenging areas in urological surgical pathology practice. A logical roadmap to T1 diagnosis would include careful evaluation of histological grade, stromal epithelial interface, characteristics of the invading epithelium, and the stroma associated responses. Tangential sectioning, crush and cautery artifacts, and associated inflammatory infiltrate are commonly encountered problems and the source of pitfalls. In this review, we outline diagnostic criteria, common pitfalls, and different histological patterns of invasion into the lamina propria. Current recommendations on reporting of biopsy and transurethral resection specimens, molecular biomarkers, clinical implications of T1 cancer diagnosis and recent developments on the T1 substaging are also discussed. Most T1 bladder cancer patients will benefit from conservative management after restaging transurethral resection of bladder and bacillus Calmette-Guérin maintenance. Patients with high risk features, such as concurrent urothelial carcinoma in situ, increased depth of invasion, lymphovascular invasion, and variant histology among others, should be considered for early cystectomy.

A four-antibody immunohistochemical panel can distinguish clinico-pathological clusters of urothelial carcinoma and reveals high concordance between primary tumor and lymph node metastases

Urothelial carcinoma of the bladder (UC) has a poor prognosis, partly because of chemotherapy resistance. Molecular classifications have shown their interest and can help to offer personalized treatment. In this study, we evaluated the feasibility of an immunohistochemical study to divide advanced UC into clinico-pathological-molecular subgroups and evaluate phenotypic correspondence between primary UC and matched lymph node metastases (LMN). An eight-antibody immunohistochemical panel was performed on UC and matched LMN from patients treated with radical cystectomy. One hundred eighty-seven UCs (100 pN0 tumor and 87 pN+ tumor) were tested. Multiple correspondence analysis showed that UC expressing GATA3 also expressed FOXA1 (p = 0.010) and did not stain for CK5/6 (p = 0.031) nor CK14 (p = 0.003). UC expressing CK14 coexpressed CK5/6 (p < 0.0001), had high Ki67 (p = 0.010) and no GATA3 (p = 0.003) nor FOXA1 (p = 0.011) expression. Loss of expression of STAG2 was associated with high Ki67 (p = 0.001). Sixty-seven percent of [CK5/6 CK14]+ [GATA3 FOAXA1]- patients had high Ki67 expression vs 37% of [GATA3 FOXA1]+ [CK5/6 CK14]- patients (p = 0.024). The majority of [CK5/6 CK14]+ [GATA3 FOAXA1]- patients (92%) had advanced disease (pT3-pT4) whilst 86% of pT1-T2 cases were [GATA3 FOXA1]+ [CK5/6 CK14]- (p = 0.041). Differential antigen expression between 63 pN+ primary tumors and their corresponding LNM showed the following concordance percentages: p53 (76%), p63 (75%), CK5/6 (65%), CK14 (89%), GATA3 (75%), FOXA1 (68%), STAG2 (65%), and Ki-67 (71%). These results support the interest of immunohistochemistry for subtype profiling in metastatic UC, using CK5/6, CK14, GATA3, and FOXA1, highlighting also few phenotypical modifications when tumor spreads to lymph nodes.

Non-Muscle-Invasive Bladder Carcinoma with Respect to Basal Versus Luminal Keratin Expression

Non-muscle-invasive bladder cancer (NMIBC) consists of transcriptional subtypes that are distinguishable from those of muscle-invasive cancer. We aimed to identify genetic signatures of NMIBC related to basal (K5/6) and luminal (K20) keratin expression. Based on immunohistochemical staining, papillary high-grade NMIBC was classified into K5/6-only (K5/6High-K20Low), K20-only (K5/6Low-K20High), double-high (K5/6High-K20High), and double-low (K5/6Low-K20Low) groups (n = 4 per group). Differentially expressed genes identified between each group using RNA sequencing were subjected to functional enrichment analyses. A public dataset was used for validation. Machine learning algorithms were implemented to predict our samples against UROMOL subtypes. Transcriptional investigation demonstrated that the K20-only group was enriched in the cell cycle, proliferation, and progression gene sets, and this result was also observed in the public dataset. The K5/6-only group was closely regulated by basal-type gene sets and showed activated invasive or adhesive functions. The double-high group was enriched in cell cycle arrest, macromolecule biosynthesis, and FGFR3 signaling. The double-low group moderately expressed genes related to cell cycle and macromolecule biosynthesis. All K20-only group tumors were classified as UROMOL "class 2" by the machine learning algorithms. K5/6 and K20 expression levels indicate the transcriptional subtypes of NMIBC. The K5/6Low-K20High expression is a marker of high-risk NMIBC.

Pure high-grade papillary urothelial bladder cancer: a luminal-like subgroup with potential for targeted therapy

PURPOSE

Non-invasive high-grade (HG) bladder cancer is a heterogeneous disease that is characterized insufficiently. First-line Bacillus Calmette-Guérin instillation fails in a substantial amount of cases and alternative bladder-preserving treatments are limited, underlining the need to promote a further molecular understanding of non-invasive HG lesions. Here, we characterized pure HG papillary urothelial bladder cancer (pure pTa HG), a potential subgroup of non-invasive HG bladder carcinomas, with regard to molecular subtype affiliation and potential for targeted therapy.

METHODS

An immunohistochemistry panel comprising luminal (KRT20, ERBB2, ESR2, GATA3) and basal (KRT5/6, KRT14) markers as well as p53 and FGFR3 was used to analyze molecular subtype affiliations of 78 pure pTa HG/papillary pT1(a) HG samples. In 66 of these, ERBB2 fluorescence in situ hybridization was performed. Additionally, targeted sequencing (31 genes) of 19 pTa HG cases was conducted, focusing on known therapeutic targets or those described to predict response to targeted therapies noted in registered clinical trials or that are already approved.

RESULTS

We found that pure pTa HG/papillary pT1(a) HG lesions were characterized by a luminal-like phenotype associated with frequent (58% of samples) moderate to high ERBB2 protein expression, rare FGFR3 alterations on genomic and protein levels, and a high frequency (89% of samples) of chromatin-modifying gene alterations. Of note, 95% of pTa HG/papillary pT1 HG cases harbored at least one potential druggable genomic alteration.

CONCLUSIONS

Our data should help guiding the selection of targeted therapies for investigation in future clinical trials and, additionally, may provide a basis for prospective mechanistic studies of pTa HG pathogenesis.

The value and limitations of urothelial bladder carcinoma molecular classifications to predict oncological outcomes and cancer treatment response: A systematic review and meta-analysis

AIM

To evaluate the predictive value of molecular subtypes on oncological outcomes and response to cancer treatment in patients with urothelial bladder carcinoma (UBC).

MATERIALS AND METHODS

A literature search using PubMed, Scopus, and Cochrane Library was conducted on April 2020 to identify relevant studies according to the preferred reporting items for systematic review and meta-analysis guidelines. The pooled overall survival (OS), cancer-specific survival (CSS), and progression-free survival were calculated using a fixed or random effects model.

RESULTS

We identified 66 studies (including 21,447 molecular subtype records) evaluating the impact of molecular classification on oncologic outcomes in patients with UBC. We found significant association of different molecular subtypes with OS, CSS, progression-free survival, recurrence-free survival, and response to treatment. Totally, 11 studies were included in the meta-analysis. Basal group and NE-like subtypes were associated with worse OS (pooled HR: 1.78, 95%CI: 1.49-2.12, and pooled HR: 2.67, 95%CI: 1.08-6.60, respectively) in patients with muscle invasive bladder cancer. Luminal group was also associated with worse CSS (pooled HR of 3.67, 95%CI: 2.19-6.14).

CONCLUSIONS

Based on these data, UBC molecular classifications are significant predictors of oncological outcomes and identify patients who are most likely to benefit from intensified or different therapies. The optimal consensus on molecular classification remains to be verified in well-designed prospective studies to allow precise prognostic and predictive value assessment.