International Opinions on Grading of Urothelial Carcinoma: A Survey Among European Association of Urology and International Society of Urological Pathology Members

Background

Grade of non-muscle-invasive bladder cancer (NMIBC) is an important prognostic factor for progression. Currently, two World Health Organization (WHO) classification systems (WHO1973, categories: grade 1-3, and WHO2004 categories: papillary urothelial neoplasm of low malignant potential [PUNLMP], low-grade [LG], high-grade [HG] carcinoma) are used.

Objective

To ask the European Association of Urology (EAU) and International Society of Urological Pathology (ISUP) members regarding their current practice and preferences of grading systems.

Design setting and participants

A web-based, anonymous questionnaire with ten questions on grading of NMIBC was created. The members of EAU and ISUP were invited to complete an online survey by the end of 2021. Thirteen experts had previously answered the same questions.

Outcome measurements and statistical analysis

The submitted answers from 214 ISUP members, 191 EAU members, and 13 experts were analyzed.

Results and limitations

Currently, 53% use only the WHO2004 system and 40% use both systems. According to most respondents, PUNLMP is a rare diagnosis with management similar to Ta-LG carcinoma. The majority (72%) would consider reverting back to WHO1973 if grading criteria were more detailed. Separate reporting of WHO1973-G3 within WHO2004-HG would influence clinical decisions for Ta and/or T1 tumors according the majority (55%). Most respondents preferred a two-tier (41%) or a three-tier (41%) grading system. The current WHO2004 grading system is supported by a minority (20%), whereas nearly half (48%) supported a hybrid three- or four-tier grading system composed of both WHO1973 and WHO2004. The survey results of the experts were comparable with ISUP and EAU respondents.

Conclusions

Both the WHO1973 and the WHO2004 grading system are still widely used. Even though opinions on the future of bladder cancer grading were strongly divided, there was limited support for WHO1973 and WHO2004 in their current formats, while the hybrid (three-tier) grading system with LG, HG-G2, and HG-G3 as categories could be considered the most promising alternative.

Patient summary

Grading of non-muscle-invasive bladder cancer (NMIBC) is a matter of ongoing debate and lacks international consensus. We surveyed urologists and pathologists of European Association of Urology and International Society of Urological Pathology on their preferences regarding NMIBC grading to generate a multidisciplinary dialogue. Both the "old" World Health Organization (WHO) 1973 and the "new" WHO2004 grading schemes are still used widely. However, continuation of both the WHO1973 and the WHO2004 system showed limited support, while a hybrid grading system composed of both the WHO1973 and the WHO2004 classification system may be considered a promising alternative.

Carboplatin Induction Chemotherapy in Clinically Lymph Node–positive Bladder Cancer

Background

There are currently no guideline recommendations regarding the treatment of cisplatin-ineligible, clinically lymph node-positive (cN+) bladder cancer (BCa).

Objective

To investigate the oncological efficacy of gemcitabine/carboplatin induction chemotherapy (IC) in comparison to cisplatin-based regimens in cN+ BCa.

Design setting and participants

This was an observational study of 369 patients with cT2-4 N1-3 M0 BCa.

Intervention

IC followed by consolidative radical cystectomy (RC).

Outcome measurements and statistical analysis

The primary endpoints were the pathological objective response (pOR; ypT0/Ta/Tis/T1 N0) rate and the pathological complete response (pCR; ypT0N0) rate. We applied 3:1 propensity score matching (PSM) to reduce selection bias. Overall survival (OS) and cancer-specific survival (CSS) were compared across groups using the Kaplan-Meier method. Associations between the treatment regimen and survival endpoints were tested in multivariable Cox regression analyses.

Results and limitations

After PSM, a cohort of 216 patients was available for analysis, of whom 162 received cisplatin-based IC and 54 gemcitabine/carboplatin IC. At RC, 54 patients (25%) had a pOR and 36 (17%) had a pCR. The 2-yr CSS was 59.8% (95% confidence interval [CI] 51.9-69%) for patients who received cisplatin-based IC versus 38.8% (95% CI 26-57.9%) for those who received gemcitabine/carboplatin. For the pOR (p = 0.8), ypN0 status at RC (p = 0.5), and cN1 BCa subgroups (p = 0.7), there was no difference in CSS between cisplatin-based IC and gemcitabine/carboplatin. In the cN1 subgroup, treatment with gemcitabine/carboplatin was not associated with shorter OS (p = 0.2) or CSS (p = 0.1) on multivariable Cox regression analysis.

Conclusions

Cisplatin-based IC seems to be superior to gemcitabine/carboplatin and should be the standard for cisplatin-eligible patients with cN+ BCa. Gemcitabine/carboplatin may be an alternative treatment for selected cisplatin-ineligible patients with cN+ BCa. In particular, selected cisplatin-ineligible patients with cN1 disease may benefit from gemcitabine/carboplatin IC.

Patient summary

In this multicenter study, we found that selected patients with bladder cancer and clinical evidence of lymph node metastasis who cannot receive standard cisplatin-based chemotherapy before surgery to remove their bladder may benefit from chemotherapy with gemcitabine/carboplatin. Patients with a single lymph node metastasis may benefit the most.

Bladder Recurrence Following Upper Tract Surgery for Urothelial Carcinoma: A Contemporary Review of Risk Factors and Management Strategies

Context

Bladder recurrences have been reported in 22-47% of patients after surgery for upper urinary tract urothelial carcinoma (UTUC). This collaborative review focuses on risk factors for and treatment strategies to reduce bladder recurrences after upper tract surgery for UTUC.

Objective

To review the current evidence on risk factors and treatment strategies for intravesical recurrence (IVR) after upper tract surgery for UTUC.

Evidence acquisition

This collaborative review is based on a literature search of PubMed/Medline, Embase, Cochrane Library, and currently available guidelines on UTUC. Relevant papers on bladder recurrence (etiology, risk factors, and management) after upper tract surgery were selected. Special attention has been paid to (1) the genetic background of bladder recurrences, (2) bladder recurrences after ureterorenoscopy (URS) with or without a biopsy, and (3) postoperative or adjuvant intravesical instillations. The literature search was performed in September 2022.

Evidence synthesis

Recent evidence supports the hypothesis that bladder recurrences after upper tract surgery for UTUC are often clonally related. Clinicopathologic risk factors (patient, tumor, and treatment related) have been identified for bladder recurrences after UTUC diagnosis. Specifically, the use of diagnostic ureteroscopy before radical nephroureterectomy (RNU) is associated with an increased risk of bladder recurrences. Further, a recent retrospective study suggests that performing a biopsy during ureteroscopy may further worsen IVR (no URS: 15.0%; URS without biopsy: 18.4%; URS with biopsy: 21.9%). Meanwhile, a single postoperative instillation of intravesical chemotherapy has been shown to be associated with a reduced bladder recurrence risk after RNU compared with no instillation (hazard ratio 0.51, 95% confidence interval 0.32-0.82). Currently, there are no data on the value of a single postoperative intravesical instillation after ureteroscopy.

Conclusions

Although based on limited retrospective data, performing URS seems to be associated with a higher risk of bladder recurrences. Future studies are warranted to assess the influence of other surgical factors as well as the role of URS biopsy or immediate postoperative intravesical chemotherapy after URS for UTUC.

Patient summary

In this paper, we review recent findings on bladder recurrences after upper tract surgery for upper urinary tract urothelial carcinoma.

Prospective Evaluation of FDG-PET/CT for On-treatment Assessment of Response to Neoadjuvant or Induction Chemotherapy in Invasive Bladder Cancer

BACKGROUND: Neoadjuvant/induction chemotherapy (NAIC) improves survival in patients with muscle-invasive bladder carcinoma (MIBC). On-treatment response assessment may aid in decisions to continue or cease NAIC. OBJECTIVE: We investigated whether 18F-fluoro-2-deoxy-D-glucose-Positron Emission Tomography/Computed Tomography (FDG-PET/CT) could predict response to NAIC and compared to contrast-enhanced Computed Tomography (CECT). METHODS: We prospectively included 83 patients treated for MIBC (i.e. high-risk cT2-4N0M0 or cT1-4N+M0-1a) between 2014 and 2018. Response to NAIC was assessed after 2-3 cycles with FDG-PET/CT (Peter-Mac and EORTC criteria) and CECT (RECIST1.1 criteria). We assessed prediction of complete pathological response (pCR; ypT0N0), complete pathological down-staging (pCD;≤ypT1N0), any down-staging from baseline (ypTN <  cTN) and progression (inoperable tumor/ypN+/M+). The reference standard was histopathological assessment or clinical follow-up. Sensitivity, specificity, and accuracy were calculated. RESULTS: Pathological response rates were 21% for pCR, 29% for pCD, and 10% progressed. All patients underwent FDG-PET/CT and 61 patients also underwent CECT (73%). Accuracy of FDG-PET/CT for prediction of pCR, pCD, and progression were 73%, 48%, and 73%, respectively. Accuracy of CECT for prediction of pCR, pCD, and progression were 78%, 65%, and 67%, respectively. Specificity of CECT was significantly higher than FDG-PET/CT for prediction of pCD and any down-staging (p = 0.007 and p = 0.022). In all other analyses, no significant differences between FDG-PET/CT and CECT were found. CONCLUSIONS: Routine FDG-PET/CT has insufficient predictive power to aid in response assessment compared to CECT.

Patterns of Recurrence and Survival After Pelvic Treatment for Locally Advanced Penile Cancer

Background

Penile cancer (PeCa) is rare, and the survival of patients with advanced disease remains poor. A better understanding of where treatment fails could aid the development of new treatment strategies.

Objective

To describe the disease course after pelvic lymph node (LN) treatment for PeCa.

Design setting and participants

We retrospectively analysed 228 patients who underwent pelvic LN treatment with curative intent from 1969 to 2016. The main treatment modalities were neoadjuvant chemotherapy, chemoradiation, and pelvic LN dissection.

Outcome measurements and statistical analysis

In the case of multiple recurrence locations, the most distant location was taken and recorded as follows: local (penis), regional (inguinal and pelvic LN), and distant (any other location). A competing risk analysis was used to calculate the time to recurrence per location, and a Kaplan-Meier analysis was used for overall survival (OS).

Results and limitations

The median follow-up of the surviving patients was 79 mo. The reason for pelvic treatment was pelvic involvement on imaging (29%), two or more tumour-positive inguinal LNs (61%), or inguinal extranodal extension (52%). More than half of the patients (61%) developed a recurrence. The median recurrence-free survival was 11 mo. The distribution was local in 9%, regional in 27%, and distant in 64% of patients. The infield control rate of nonsystemically treated patients was 61% (113/184). From the start of pelvic treatment, the median OS was 17 mo (95% confidence interval 12-22). After regional or distant recurrence, all but one patient died of PeCa with median OS after a recurrence of 4.4 (regional) and 3.1 (distant) mo. This study is limited by its retrospective nature.

Conclusions

The prognosis of PeCa patients treated on their pelvis who recur despite locoregional treatment is poor. The tendency for systemic spread emphasises the need for more effective systemic treatment strategies.

Patient summary

In this report, we looked at the outcomes of penile cancer patients in an expert centre undergoing various treatments on their pelvis. We found that survival is poor after recurrence despite locoregional treatment. Therefore, better systemic treatments are necessary.

Non-metastatic muscle-invasive bladder cancer: the role of age in receiving treatment with curative intent

OBJECTIVES

To evaluate which patient and tumour characteristics are associated with remaining untreated in patients with potentially curable, non-metastatic muscle-invasive bladder cancer (MIBC), and to compare survival of untreated vs treated patients with similar characteristics.

PATIENTS AND METHODS

For this cohort study, 15 047 patients diagnosed with cT2-T4aN0/xM0/x urothelial MIBC between 2005 and 2019 were identified in the Netherlands Cancer Registry. Factors associated with remaining untreated were identified using logistic regression analyses. Interhospital variation was assessed using multilevel analysis. Using a propensity score, the median overall survival (mOS) of untreated and treated patients was evaluated. Analyses were stratified by age (&lt;75 vs ≥75 years).

RESULTS

One-third of patients aged ≥75 years remained untreated; increasing age, worse performance status, worse renal function, cT4a stage and previous radiotherapy in the abdomen/pelvic area increased the odds of remaining untreated. One in 10 patients aged &lt;75 years remained untreated; significant associations were only found for performance status, renal function and cT4a stage. Interhospital variation for remaining untreated was largest for patients aged ≥75 years, ranging from 37% to 69% (case-mix-adjusted). Irrespective of age, mOS was significantly worse for untreated patients: 6.4 months (95% confidence interval [CI] 5.1-7.3) vs 16.0 months (95% CI 13.5-19.1) for treated patients.

CONCLUSION

On average, one in five patients with non-metastatic MIBC remained untreated. Untreated patients were generally older and had a more unfavourable prognostic profile. Untreated patients had significantly worse overall survival, regardless of age. Age alone should therefore not affect treatment decision-making. Considering the large interhospital variation, a proportion of untreated patients might be wrongfully denied life-prolonging treatment.

Sensitivity and Specificity in Urine Bladder Cancer Markers – Is it that Simple?

Marker research and, in particular urine bladder cancer marker research throughout the past three decades, devours enormous scientific resources in terms of manpower (not to mention time spent on reviewing and editorial efforts) and financial resources finally generating large numbers of manuscripts without affecting clinical decision making. This is mirrored by the fact that current guidelines do not recommend marker use due to missing level 1 evidence. Although we recognize the problems and obstacles, the authors of this commentary feel that the time has come to abandon the current procedures and move on to prospective trial designs implementing marker results into clinical decision making. Our thoughts and concerns are summarized in this comment.

Abstract B07: A long noncoding RNA-based genomic classifier identifies a subset of luminal muscle-invasive bladder cancer patients with favorable prognosis

Background: Muscle-invasive bladder cancer (MIBC) is a heterogeneous disease and gene expression profiling has identified different molecular subtypes, each having distinct biologic and clinicopathologic characteristics. Subtyping MIBC has primarily been messenger RNA (mRNA)-based, although noncoding RNAs, including long noncoding RNAs (lncRNAs), have potential utility in providing additional resolution to current molecular subtyping models.

Materials and Methods: The expression profiles of over 6,000 lncRNAs were quantified from whole-transcriptome microarray data of a MIBC patient cohort treated by neoadjuvant chemotherapy (NAC) and radical cystectomy (N=223). Unsupervised consensus clustering of the most highly variant lncRNAs identified a four-cluster solution, which was further characterized using a panel of MIBC biomarkers, gene signatures, and survival analysis. The four-cluster consensus was validated using the publicly available The Cancer Genome Atlas (TCGA) radical cystectomy cohort (N=405). A single-sample genomic classifier (GC) was trained using ridge-penalized logistic regression and then validated in two independent patient cohorts (N=255 and N=94).

Results: In the NAC and TCGA cohorts, survival analysis of a lncRNA-based consensus cluster solution revealed a lncRNA-cluster (LC3) with strikingly good prognosis that was enriched for tumors of the luminal-papillary mRNA subtype. In both cohorts, the luminal-papillary tumors from this cluster (LPL-C3) were clinically less aggressive than other luminal-papillary tumors. Patients having LPL-C3 tumors were younger and had more frequent organ-confined, node-negative disease than other luminal-papillary tumors. LPL-C3 tumors were characterized by enhanced FGFR3 pathway activity, wild-type P53 expression, and robust SHH signaling. In the TCGA cohort, LPL-C3 tumors were also enriched for FGFR3 mutations and depleted for TP53 and RB1 mutations. A GC trained to identify these LPL-C3 patients showed robust performance in two validation cohorts.

Conclusions: Using lncRNA expression profiling, we identified a biologically distinct subgroup of luminal-papillary MIBC with less-aggressive molecular characteristics and favorable prognosis. These data suggest that lncRNAs can provide additional information in resolving higher-resolution subtypes for more precise patient management strategies.

Citation Format: Joep J. de Jong, Yang Liu, Roland Seiler, A. Gordon Robertson, Michiel S. van der Heijden, Jonathan L. Wright, James Douglas, Marc Dall'Era, Simon J. Crabb, Bas W.G. van Rhijn, Kim E.M. van Kessel, Elai Davicioni, Yair Lotan, Ellen C. Zwarthoff, Peter C. Black, Joost L. Boormans, Ewan A. Gibb. A long noncoding RNA-based genomic classifier identifies a subset of luminal muscle-invasive bladder cancer patients with favorable prognosis [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2019 May 18-21; Denver, CO. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(15_Suppl):Abstract nr B07.

Biomarker analysis and updated clinical follow-up of preoperative ipilimumab (ipi) plus nivolumab (nivo) in stage III urothelial cancer (NABUCCO)

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Background: Encouraging pathological complete response (pCR) rates were observed in trials testing neoadjuvant pembrolizumab or atezolizumab in urothelial cancer (UC). In cT3-4N0 tumors, pCR to atezolizumab was only 17% and restricted to tumors showing characteristics of preexisting T cell immunity. In NABUCCO, we aimed to increase response to pre-operative checkpoint blockade, particularly in high risk patients (pts), by combining ipi plus nivo in stage III UC. We previously reported pCR in 46% and downstaging to no remaining invasive disease in 58% (ESMO2019). Here, we present biomarker analyses and updated clinical follow-up (FU) data. Methods: Twenty four stage III (cT3-4aN0 or cT2-4aN1-3) UC pts who were unfit to receive cisplatin-based chemotherapy or refused, were treated with ipi 3 mg/kg (day 1), ipi 3 mg/kg + nivo 1 mg/kg (day 22), and nivo 3 mg/kg (day 43), followed by resection. The primary endpoint was feasibility (resection < 12 weeks). Efficacy (pCR), safety and biomarker analysis were secondary endpoints. Whole-exome sequencing (WES) was done on baseline tumor samples and local lymph node (LN) metastases showing no response. RNA-seq and multiplex immunofluorescence (mIF) for immune cell markers were done pre- and post-therapy. Results: After a median FU of 15.6 months, 2 pts relapsed (both non-pCR); 1 of these 2 pts died of metastatic disease. Tumors showing complete response (CR, for biomarker analysis defined as pCR, CIS or pTa) had a significantly higher tumor mutational burden than non-CR tumors. CR to ipi+nivo was independent of baseline CD8 T-cell presence. There was no difference between CR and non-CR tumors in baseline immune gene signatures, such as interferon gamma and T-effector signatures. Surprisingly, exploratory gene expression analysis revealed that non-CR was associated with a baseline B cell immune signature, particularly immunoglobulins and genes involved in B cell receptor signaling. CD20 positive cells (by mIF) and presence of tertiary lymphoid structures (TLS) at baseline were also associated with non-CR. Upon treatment with ipi+nivo, early and mature TLS increased significantly in responding tumors. A subset of pts showed CR in the bladder, but non-CR in a local LN tumor focus. WES revealed that these LN metastases were genetically different from the primary tumor bulk. Conclusions: At 15.6 months follow-up, recurrence after pre-operative ipi+nivo was low. Pathological complete response was not restricted to tumors exhibiting preexisting T cell immunity. Clinical trial information: NCT03387761 .

Muscle-invasive bladder cancer: Molecular subtypes and response to neoadjuvant chemotherapy

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Background: Molecular subtypes of muscle-invasive bladder cancers (MIBC) have recently been discovered based on gene expression. We investigated the impact of different subtyping methods on response to neoadjuvant cisplatin-based chemotherapy (NAC) and developed a single sample model for subtyping. Methods: Transcriptome-wide microarray analysis was conducted on pre-NAC transurethral resection (TUR) specimens of 223 patients with MIBC who received NAC followed by cystectomy at 5 centers. The specimens were classified according to four published methods for molecular subtype (UNC, MDA, TCGA, Lund). Overall survival (OS) for each subtype was compared between NAC patients in this study and non-NAC patients from the provisional TCGA. A genomic classifier (GSC) was trained to predict subtype in a single sample model and validated in independent NAC (2 centers) and non-NAC datasets. Results: The models generated subtype calls similar to previously published ratios. Concordance of a given subtype between the different methods was high. Luminal tumors had the best OS independent of NAC. Patients with tumors classified as UNC basal, MDA basal and TCGA cluster III experienced the greatest improvement in OS after NAC compared to surgery alone. Tumors assigned as UNC claudin-low had the worst OS irrespective of treatment regimen (p=0.005). GSC accurately predicted four classes (luminal, luminal-infiltrated, basal, claudin-low) and the differential impact of a basal subtype on patient OS in NAC (3-yr survival of 75.2%; p=0.001) and non-NAC (3-yr survival of 42.4%; p=0.014) cohorts could be validated. Conclusions: The benefit of NAC varies between molecular subtypes. The good prognosis of luminal/cluster I tumors could not be improved with NAC, which suggests these patients may be managed best with surgery alone. The prognosis of patients with basal tumors improved the most when treated with NAC compared to surgery alone. Poor OS of claudin-low tumors even after NAC implies that these tumors are resistant to cisplatin-based chemotherapy, and these patients should be included in protocols investigating alternative treatment options like immunotherapy. Further validation prior to clinical implementation is needed.

A phase I study of chemoradiation with weekly panitumumab following neoadjuvant chemotherapy and pelvic lymph node dissection as an organ preserving treatment of invasive bladder cancer

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Background: Radical Cystectomy (RC) is the standard treatment of Invasive Bladder Cancer (IBC). Although organ sparing, external beam Radiation Treatment (RT) alone is considered inferior to RC. Since the Epidermal Growth Factor receptor (EGFr) is frequently overexpressed in IBC, combined EGFr inhibition by Panitumumab (P) and RT might improve treatment outcome. In this study, the safety and efficacy of concurrent RT and P (RT/P) following Neoadjuvant Chemotherapy (NAC) and Pelvic Lymph Node Dissection (PLND) was evaluated. Methods: cT2-4N0-2M0 or cT1N1-2M0 bladder cancer patients were enrolled in the study. NAC consisted of a maximum of 4 cycles platinum-based chemotherapy. cN0 patients received NAC after PLND, while cN+ patients (confirmed by fine needle aspiration) received NAC prior to PLND. RT/P consisted of concurrent P (7 weekly doses of 2.5 mg/kg) and bladder RT (66Gy in 33 fractions). Primary end-points were treatment-related toxicity and complete clinical response (CR) assessed by Computed Tomography and cystoscopy 3 months after therapy completion. Partial response (PR) was defined as cT < 2N0. Results: A total of 31 patients were included (mean age: 60±10 years), 3/31 patients were cN1-2. Three patients discontinued NAC after 3 cycles due to toxicity. After NAC (24 cisplatin-based and 7 gemcitabine/carboplatin) 13 (41.9%) patients had remaining visible disease. All patients completed RT, while 4/31 patients terminated P prematurely (2-6 doses) due to toxicity. Preliminary response results after RT/P were available for 29/31 patients. Twenty-six/29 (89.7%) patients had a CR, 3 patients PR (10.3%) of which 2 were treated with transurethral resection and intravesical treatment (TaG1-2) and 1 patient underwent immediate cystectomy after histologic confirmation of T1G3. Conclusions: These preliminary results suggest that concurrent P and RT following NAC and PLND is an organ-preserving option for IBC. Toxicity, EGFr expression, mutational status and long-term oncologic outcomes have to be awaited. Clinical trial information: NL31148.031.10.