Novel neoadjuvant therapy paradigms for bladder cancer: results from the National Cancer Center Institute Forum

Molecular Oncology of Bladder Cancer from Inception to Modern Perspective

Within the last forty years, seminal contributions have been made in the areas of bladder cancer (BC) biology, driver genes, molecular profiling, biomarkers, and therapeutic targets for improving personalized patient care. This overview includes seminal discoveries and advances in the molecular oncology of BC. Starting with the concept of divergent molecular pathways for the development of low- and high-grade bladder tumors, field cancerization versus clonality of bladder tumors, cancer driver genes/mutations, genetic polymorphisms, and bacillus Calmette-Guérin (BCG) as an early form of immunotherapy are some of the conceptual contributions towards improving patient care. Although beginning with a promise of predicting prognosis and individualizing treatments, "-omic" approaches and molecular subtypes have revealed the importance of BC stem cells, lineage plasticity, and intra-tumor heterogeneity as the next frontiers for realizing individualized patient care. Along with urine as the optimal non-invasive liquid biopsy, BC is at the forefront of the biomarker field. If the goal is to reduce the number of cystoscopies but not to replace them for monitoring recurrence and asymptomatic microscopic hematuria, a BC marker may reach clinical acceptance. As advances in the molecular oncology of BC continue, the next twenty-five years should significantly advance personalized care for BC patients.

Management of Muscle-invasive Bladder Cancer in the 2020s: Challenges and Perspectives

Despite an increased use of neoadjuvant and adjuvant chemotherapy, the long-term survival rates after radical cystectomy or trimodal therapy (TMT) for muscle-invasive bladder cancer (MIBC) remain basically unchanged for decades. Detection and effective treatment of micrometastatic disease are still a clinical dilemma. Assessment of circulating tumor DNA in combination with improved imaging modalities may improve the prediction of micrometastatic disease. Different genetic subtypes of MIBC show varying degrees of chemosensitivity. Further progress needs to be made in order to develop a common molecular classifier that can be used easily for daily clinical decision making. With the advent on immuno-oncology, bladder-sparing protocols are on the rise as an alternative to surgery. The extent of transurethral bladder tumor resection has a marked impact on the response rates to TMT and neoadjuvant chemotherapy. This review focuses on strategies regarding how to integrate surgery, radiotherapy, and molecular-based systemic treatment for improved oncological outcomes of patients with MIBC. PATIENT SUMMARY: Effective treatment of micrometastatic disease is the key to improved oncological outcomes in muscle-invasive bladder cancer and requires a multidisciplinary approach.

Molecular Predictors of Complete Response Following Neoadjuvant Chemotherapy in Urothelial Carcinoma of the Bladder and Upper Tracts

Urothelial carcinoma of the bladder (UCB) and upper tracts (UTUC) is often regarded as one entity and is managed generally with similar principles. While neoadjuvant chemotherapy (NAC) followed by radical cystectomy (RC) is an established standard of care in UCB, strong evidence for a similar approach is lacking in UTUC. The longest survival is seen in patients with complete response (pT0) on pathological examination of the RC specimen, but impact of delayed RC in nonresponders may be detrimental. The rate of pT0 following NAC in UTUC is considerably lower than that in UCB due to differences in access and instrumentation. Molecular markers have been evaluated to try to predict response to chemotherapy to reduce unnecessary treatment and expedite different treatment for nonresponders. A variety of potential biomarkers have been evaluated to predict response to cisplatin based chemotherapy including DNA repair genes (ATM, RB1, FANCC, ERCC2, BRCA1, and ERCC1), regulators of apoptosis (survivin, Bcl-xL, and emmprin), receptor tyrosine kinases (EGFR and erbB2), genes involved in cellular efflux (MDR1 and CTR1), in addition to molecular subtypes (Basal, luminal, and p53-like). The current state of the literature on the prediction of response to NAC based on the presence of these biomarkers is discussed in this review.

SIU-ICUD consultation on bladder cancer: basic science

PURPOSE

To provide a condensed summary of the Basic Science chapter that was included in the Third International Consultation on Bladder Cancer.

METHODS

World bladder cancer basic science experts used the published literature to create summaries of recent progress in their areas of expertise.

RESULTS

The completion of several large-scale genomics projects coupled with a strong collaborative culture within the research community and the exciting clinical activity of immune checkpoint blockade have combined to transform the bladder cancer research landscape. Bladder cancer molecular subtypes and the presence of specific DNA alterations provide important information about disease heterogeneity that has direct implications for clinical management, and some can be targeted by compounds that are already clinically available. Tests are being developed that can measure many of these alterations non-invasively in peripheral blood or urine, raising confidence that they could be used as biomarkers for surveillance and monitoring the effects of local and systemic therapies.

CONCLUSIONS

Although the bulk of the mechanistic work lies ahead, the genomics results have created a hypothesis-generating description of bladder cancer heterogeneity that has set the stage for deeper mechanistic studies, and they have already provided us with extremely attractive candidate biomarkers to guide clinical practice. Here, we will summarize the recent progress in basic bladder cancer research and highlight near-term opportunities for the future.

Discerning Patterns and Quality of Neoadjuvant Chemotherapy Use Among Patients with Muscle-invasive Bladder Cancer

BACKGROUND

Neoadjuvant chemotherapy is underutilized in bladder cancer patients who undergo radical cystectomy. However, the quality of regimens used in this setting remains largely unknown.

OBJECTIVE

To determine utilization treatment patterns and survival outcomes according to regimens administered.

DESIGN, SETTING, AND PATIENTS

We used the Surveillance, Epidemiology and End Results (SEER)-Medicare linked database to identify patients diagnosed with clinical stage TII-IV bladder cancer from January 1, 2001 to December 31, 2011.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Temporal trends were assessed using the Cochran-Armitage test. Multivariable logistic regression models were used to identify predictors for neoadjuvant chemotherapy use. Cox proportional hazards models were used to compare overall survival according to regimens administered.

RESULTS AND LIMITATIONS

Of 2738 patients treated with radical cystectomy, 344 (12.6%) received neoadjuvant chemotherapy. The agents most commonly used were gemcitabine (72.3%), cisplatin (55.2%), and carboplatin (31.1%). The regimens most commonly used were gemcitabine-cisplatin (45.3%), gemcitabine-carboplatin (24.1%), and methotrexate, vinblastine, doxorubicin, and cisplatin (M-VAC; 6.7%). Use of neoadjuvant chemotherapy more than tripled during the study period, from 5.7% in 2001 to 17.3% in 2011 (p<0.001). The quality of the regimen administered impacted survival outcomes, as M-VAC use was significantly associated with better overall survival among patients diagnosed with stage II bladder cancer (hazard ratio 0.24, 95% confidence interval 0.07-0.86; p=0.030]. Limitations include the limited ability of retrospective analysis to control for selection bias.

CONCLUSIONS

Neoadjuvant chemotherapy was underused, and the quality of neoadjuvant chemotherapy regimens administered for bladder cancer was inconsistent with guideline recommendations. These findings are important when interpreting population-based data on the use of chemotherapy and extrapolating survival outcomes.

PATIENT SUMMARY

In a large population-based study, 12.6% of patients undergoing radical cystectomy for bladder cancer received neoadjuvant chemotherapy, half of whom received guideline-recommended regimens. The quality of the regimen impacted survival outcomes, as use of cisplatin-based chemotherapy was significantly associated with better overall survival among patients diagnosed with stage II bladder cancer. However, <1% of radical cystectomy patients received this regimen.

Optimal Timing of Chemotherapy and Surgery in Patients with Muscle-Invasive Bladder Cancer and Upper Urinary Tract Urothelial Carcinoma

Radical cystectomy with bilateral pelvic lymph node dissection is the standard of care for patients with clinically localized muscle-invasive bladder cancer. Survival after radical cystectomy is associated with final pathologic staging. Survival decreases with increasing pT stage because of the presence of occult micrometastases, indicating the need for systemic chemotherapy. Systemic chemotherapy is delivered as either neoadjuvant therapy preoperatively, or as adjuvant therapy postoperatively. This article reviews the evidence for neoadjuvant and adjuvant chemotherapy for the treatment of muscle-invasive bladder and upper tract urothelial cancer and offers recommendations based on these data and recently updated clinical guidelines.

Pharmacogenomic considerations in the treatment of muscle-invasive bladder cancer

Recent advances in next-generation sequencing techniques have greatly improved our understanding of the genomic alterations in bladder cancer. Cisplatin-based chemotherapy provides a viable treatment option in the neoadjuvant, adjuvant and metastatic setting in a selected group of patients, but chemoresistance is a major problem. The underlying mechanisms of treatment resistance are poorly understood and elucidating these pathways will subsequently lead to improved patient selection, less unnecessary drug-related toxicity, improved patient outcome and decreased healthcare costs. This review provides an overview of mechanisms of chemoresistance and describes the current knowledge on how the genomic landscape influences therapy outcome in muscle-invasive bladder cancer patients.

Toward personalized management in bladder cancer: the promise of novel molecular taxonomy

Empowered by the recent advances in next generation sequencing and bioinformatics technology, an unprecedented wave of integrated transcriptomic and genomic studies have impacted the field of bladder cancer. These studies not only have confirmed previously charted genetic pathways in bladder cancer development but also have led to the discovery of numerous additional crucial driver genetic alterations. As a result, a novel genomic-based taxonomy is emerging that promises to better define clinically relevant intrinsic subtypes of bladder cancer. The current review is an update on the above advances and their significant implications on the future of bladder cancer patient management.

Molecular biomarkers to predict response to neoadjuvant chemotherapy for bladder cancer

Cystectomy is the gold standard for treatment of localized muscle-invasive bladder cancer. However, about 50% of patients develop metastases within 2years after cystectomy and subsequently die for the disease. Neoadjuvant cisplatin-based chemotherapy before cystectomy improves the overall survival in patients with muscle-invasive bladder cancer, and pathological response to neoadjuvant treatment (downstaging to ⩽pT1 at cystectomy) is a strong predictor of better disease-specific survival. Nevertheless, some patients do not benefit from neoadjuvant therapy. The identification of reliable biomarkers that could enable the clinicians to identify patients who will really benefit from neoadjuvant chemotherapy is a major issue. This approach could lead to individualized therapy, in order to optimize the chance of response, avoiding the impact of neoadjuvant treatment on quality of life and the delay of cystectomy in non-responder patients. However, no molecular predictive biomarkers have shown clinical utility. This paper aims to review currently available data about biomarkers predictive of response to neoadjuvant chemotherapy in muscle-invasive bladder cancer.

Platinum Concentration and Pathologic Response to Cisplatin-Based Neoadjuvant Chemotherapy in Muscle-Invasive Bladder Cancer

Background

Platinum (Pt)-based chemotherapy is the standard of care for muscle-invasive bladder cancer (MIBC). However, resistance is a major limitation. Reduced intratumoral drug accumulation is an important mechanism of platinum resistance. Our group previously demonstrated a significant correlation between tissue Pt concentration and tumor response to Pt-based neoadjuvant chemotherapy (NAC) in lung cancer. We hypothesized that increased Pt concentration in radical cystectomy (RC) specimens would correlate with improved pathologic response to Pt-based NAC in MIBC.

Methods

A cohort of 19 clinically annotated, archived, fresh frozen RC specimens from patients with MIBC treated with Pt-based NAC was identified [ypT0 (pathologic complete response, pCR), N = 4; ≤ypT1N0M0 (pathologic partial response, pPR), N = 6; ≥ypT2 (minimal pathologic response/progression), N = 9)]. RC specimens from 2 patients with MIBC who did not receive NAC and 1 treated with a non-Pt containing NAC regimen were used as negative controls. Total Pt concentration in normal adjacent urothelial tissue and bladder tumors from RC specimens was measured by flameless atomic absorption spectrophotometry.

Results

Total Pt concentration in normal urothelium differed by tumor pathologic response (P = 0.011). Specimens with pCR had the highest Pt concentrations compared to those with pPR (P = 0.0095) or no response/progression (P = 0.020). There was no significant difference in Pt levels in normal urothelium and tumor between pPR and no response/progression groups (P = 0.37; P = 0.25, respectively). Conclusions: Our finding of increased intracellular Pt in RC specimens with pCR following NAC for MIBC compared to those with residual disease suggests that enhanced Pt accumulation may be an important determinant of Pt sensitivity. Factors that modulate intracellular Pt concentration, such as expression of Pt transporters, warrant further investigation as predictive biomarkers of response to Pt-based NAC in MIBC.

Genetic subtypes of invasive bladder cancer

PURPOSE OF REVIEW

Recently completed cancer genomics projects identified intrinsic subtypes in muscle-invasive bladder cancers. Here we will describe the studies that led to their discovery and review their biological and clinical properties.

RECENT FINDINGS

Whole genome mRNA expression profiling and unsupervised hierarchical cluster analyses identified intrinsic basal and luminal subtypes in muscle-invasive bladder cancers that are similar to the ones found in breast cancer. Tumors within each subtype have distinct responses to conventional cisplatin-based combination chemotherapy, and they contain gene expression signatures and DNA alterations that may render them vulnerable to clinically available targeted therapies.

SUMMARY

Like their breast cancer counterparts, basal bladder cancers are characterized by poor clinical outcomes in the absence of effective systemic therapy, but a large fraction of them do respond to neoadjuvant chemotherapy, suggesting that the tumors should be managed aggressively. On the contrary, tumors that belong to the 'p53-like' subtype tend to be chemoresistant, so patients with these tumors should probably be managed differently. It seems likely that prospective identification of tumor intrinsic subtype membership could complement the use of DNA-based biomarkers to identify the groups of patients who will benefit the most from chemotherapy and targeted agents.

Emerging Bladder Cancer Biomarkers and Targets of Therapy

Bladder cancer is a heterogeneous disease characterized by complex networks of molecular alterations and gene expression. This review summarizes some of the recent genomic studies that have further advanced the understanding of the pathways driving bladder cancer, highlighting several important biomarkers and potential targeted therapeutic strategies that are now in clinical trials. In addition, noninvasive techniques to evaluate biomarkers in patients' urine and serum for early detection and surveillance are discussed.

Feasibility outcomes of a presurgical randomized controlled trial exploring the impact of caloric restriction and increased physical activity versus a wait-list control on tumor characteristics and circulating biomarkers in men electing prostatectomy for prostate cancer

Background

Obesity is associated with tumor aggressiveness and disease-specific mortality for more than 15 defined malignancies, including prostate cancer. Preclinical studies suggest that weight loss from caloric restriction and increased physical activity may suppress hormonal, energy-sensing, and inflammatory factors that drive neoplastic progression; however, exact mechanisms are yet to be determined, and experiments in humans are limited.

Methods

We conducted a randomized controlled trial among 40 overweight or obese, newly-diagnosed prostate cancer patients who elected prostatectomy to explore feasibility of a presurgical weight loss intervention that promoted a weight loss of roughly one kg. week⁻¹ via caloric restriction and physical activity, as well as to assess effects on tumor biology and circulating biomarkers. Measures of feasibility (accrual, retention, adherence, and safety) were primary endpoints. Exploratory aims were directed at the intervention’s effect on tumor proliferation (Ki-67) and other tumor markers (activated caspase-3, insulin and androgen receptors, VEGF, TNFβ, NFκB, and 4E-BP1), circulating biomarkers (PSA, insulin, glucose, VEGF, TNFβ, leptin, SHBG, and testosterone), lymphocytic gene expression of corresponding factors and cellular bioenergetics in neutrophils, and effects on the gut microbiome. Consenting patients were randomized in a 1:1 ratio to either: 1) weight loss via a healthful, guidelines-based diet and exercise regimen; or 2) a wait-list control. While biological testing is currently ongoing, this paper details our methods and feasibility outcomes.

Results

The accrual target was met after screening 101 cases (enrollment rate: 39.6 %). Other outcomes included a retention rate of 85 %, excellent adherence (95 %), and no serious reported adverse events. No significant differences by age, race, or weight status were noted between enrollees vs. non-enrollees. The most common reasons for non-participation were “too busy” (30 %), medical exclusions (21 %), and “distance” (16 %).

Conclusions

Presurgical trials offer a means to study the impact of diet and exercise interventions directly on tumor tissue, and other host factors that are feasible and safe, though modifications are needed to conduct trials within an abbreviated period of time and via distance medicine-based approaches. Pre-surgical trials are critical to elucidate the impact of lifestyle interventions on specific mechanisms that mediate carcinogenesis and which can be used subsequently as therapeutic targets.

Trial registration

NCT01886677

The Role of HMGB1 in Radioresistance of Bladder Cancer

Although radical cystectomy surgery is the standard-of-care for muscle-invasive bladder cancer, it entails complete removal of the bladder and surrounding organs which leads to substantial loss in the quality-of-life of patients. Radiotherapy, which spares the bladder, would be a more appropriate treatment modality if we can utilize molecular markers to select patients with better response to radiation. In this study, we investigate a protein called high mobility group box protein 1 (HMGB1) as a predictive marker for radiotherapy response in bladder cancer. Our in vitro results indicate a positive correlation between higher levels of HMGB1 protein and resistance to radiation in various cell lines. Upon HMGB1 protein knockdown, highly significant (>1.5-fold) sensitization to radiotherapy was achieved. We saw that loss of HMGB1 was associated with at least two times higher (P < 0.001) DNA damage in cell lines postradiation. Our results also depicted that autophagy was inhibited more than 3-fold (P < 0.001) upon HMGB1 knockdown, implicating its role in autophagy as another cause of bladder cancer radioresistance. Further validation was done in vivo by conducting mouse tumor xenograft experiments, where HMGB1 knockdown tumors showed a significantly better (P < 0.001) response to radiotherapy and decreased autophagy (shown by P62 staining) as compared with controls. The cumulative findings of our in vitro and in vivo studies highlight the significance of HMGB1 as a radiation response marker as well as its utility in radiosensitization of bladder cancer.

Final Pathological Stage after Neoadjuvant Chemotherapy and Radical Cystectomy for Bladder Cancer-Does pT0 Predict Better Survival than pTa/Tis/T1?

PURPOSE

We assessed survival dependent on pathological response after neoadjuvant chemotherapy in a large multicenter patient cohort, with a particular focus on the difference between the absence of residual cancer (pT0) and the presence of only nonmuscle invasive residual cancer (pTa, pTis, pT1).

MATERIALS AND METHODS

We retrospectively reviewed records of patients with urothelial cancer who received neoadjuvant chemotherapy and underwent radical cystectomy at 19 contributing institutions from 2000 to 2013. Patients with cT2-4aN0M0 and eventual pN0 disease were selected for this analysis. Estimated overall survival was compared between patients with pT0 and pTa/Tis/T1 disease. A multivariable Cox proportional hazards regression model for overall survival was generated to evaluate hazard ratios for variables of interest.

RESULTS

Of 1,543 patients treated with neoadjuvant chemotherapy and radical cystectomy during the study period 257 had pT0N0 and 207 had pTa/Tis/T1N0 disease. The Kaplan-Meier mean estimates of overall survival for pT0 and pTa/Tis/T1 cases were 186.7 months (95% CI 145.9-227.6, median 241.1) and 138 months (95% CI 118.2-157.8, median 187.4), respectively (p=0.58). In the Cox proportional hazards regression model for overall survival pTa/Tis/T1N0 status (HR 0.36, 95% CI 0.23-0.67) and pT0N0 status (HR 0.28, 95% CI 0.17-0.47) compared to pT2N0 pathology, positive surgical margin (HR 1.75, 95% CI 1.07-2.86), and receiving a methotrexate, vinblastine, doxorubicin and cisplatin regimen compared to an "other" regimen (HR 0.45, 95% CI 0.27-0.76) were predictors of overall survival.

CONCLUSIONS

pTa/Tis/T1N0 and pT0N0 stage on the final cystectomy specimen are strong predictors of survival in patients treated with neoadjuvant chemotherapy and radical cystectomy. We did not discern a statistically significant difference in overall survival when comparing these 2 end points.

Chemotherapy for Invasive Bladder Cancer: Five Simple Rules Learned Over 30 Years

Invasive, clinically non-metastatic bladder cancer has a cure rate of only 50% , when all T stages are considered. The pattern of relapse is dominated by systemic spread, provided that optimal surgery is practiced. Occult metastases are thus most likely to be present at first presentation. For more than 30 years, therapeutic strategies have focused on the use of systemic chemotherapy before, during or after loco-regional therapy to produce cure. More aggressive surgery and more precise radiation techniques in addition to improved chemotherapy have also been tested to improve cure rates. Genetic analysis has focused on prediction and prognostication, without yet having a major impact on outcomes. New agents have been tested in the neoadjuvant and adjuvant setting, but have not yet proven superior to standard algorithms, such as neoadjuvant MVAC chemotherapy. Many studies have tested ineffective metastatic regimens in the neoadjuvant setting without success, giving rise to the maxim that ignoring logical rules of investigation will not advance clinical practice. Leveraging molecular prognostication and immune responsiveness of urothelial cancer may produce the next era of progress. Five simple rules are proposed to guide the development of future studies.