Emerging drugs for urothelial (bladder) cancer

INTRODUCTION

Metastatic urothelial carcinoma has been associated with poor prognosis and a median survival of approximately 12-14 months with standard therapy. Treatment options for decades have been limited to platinum based chemotherapy as first line with few therapeutic options available to the majority who will ultimately progress beyond platinum. Areas covered: This review focuses on the various targeted, antiangiogenic, chemotherapeutic and immunotherapeutic agents currently being developed for the treatment of urothelial carcinoma. Expert opinion: Incorporation of systemic immunotherapy into the treatment of urothelial carcinoma has already fundamentally changed the treatment of this disease. The landscape is rapidly changing and it is likely that immunotherapy will be incorporated into therapy in earlier disease states and in novel combinations. Outcomes in urothelial carcinoma have improved and likely to improve further with ongoing and future clinical research that is discussed in this review.

Randomized Phase II Study Investigating Pazopanib Versus Weekly Paclitaxel in Relapsed or Progressive Urothelial Cancer

Purpose Two previous single-arm trials have drawn conflicting conclusions regarding the activity of pazopanib in urothelial cancers after failure of platinum-based chemotherapy. Patients and Methods This randomized (1:1) open-label phase II trial compared the efficacy of pazopanib 800 mg orally with paclitaxel (80 mg/m2 days 1, 8, and 15 every 28 days) in the second-line setting. The primary end point was overall survival (OS). Results Between August 2012 and October 2014, 131 patients, out of 140 planned, were randomly assigned. The study was terminated early on the recommendation of the independent data monitoring committee because of futility. Final analysis after the preplanned number of deaths (n = 110) occurred after a median follow-up of 18 months. One hundred fifteen deaths had occurred at the final data extract presented here. Median OS was 8.0 months for paclitaxel (80% CI, 6.9 to 9.7 months) and 4.7 months for pazopanib (80% CI, 4.2 to 6.4 months). The hazard ratio (HR) adjusted for baseline stratification factors was 1.28 (80% CI, 0.99 to 1.67; one-sided P = .89). Median progression-free survival was 4.1 months for paclitaxel (80% CI, 3.0 to 5.6 months) and 3.1 months for pazopanib (80% CI, 2.7 to 4.6 months; HR, 1.09; 80% CI, 0.85 to 1.40; one-sided P = .67). Discontinuations for toxicity occurred in 7.8% and 23.1% for paclitaxel and pazopanib, respectively. Conclusion Pazopanib did not have greater efficacy than paclitaxel in the second-line treatment of urothelial cancers. There was a trend toward superior OS for paclitaxel.

Systemic therapy in bladder cancer

Systemic chemotherapy is essential for the management of muscle-invasive bladder cancer (MIBC) and metastatic bladder cancer (BCa). Neoadjuvant chemotherapy is key to the management of MIBC with many cisplatin-based regimens. Adjuvant chemotherapy may be considered for selected patients who did not receive neoadjuvant therapy. Systemic chemotherapy with radiotherapy is a critical component of a trimodal bladder-preserving approach and is superior to radiotherapy alone. Cisplatin-based chemotherapy has been the mainstay for metastatic BCa. Immunotherapy in the form of checkpoint inhibitors is a promising new drug for the treatment of BCa. Molecular characterization of each individual BCa is likely to lead to a target-directed therapeutic revolution.

Targeted therapies in the treatment of urothelial cancers

Progress has been slow in systemic management of locally advanced and metastatic bladder cancer over the past 20 years. However, the recent approval of immunotherapy with atezolizumab and nivolumab for second-line salvage therapy may usher in an era of more rapid improvement. Systemic treatment is suboptimal and is an area of substantial unmet medical need. The recent findings from The Cancer Genome Atlas project revealed promising pathways that may be amenable to targeted therapies. Promising results with treatment using vascular endothelial growth factor inhibitors such as ramucirumab, sunitinib or bevacizumab, and human epidermal growth factor receptor 2 targeted therapies, epidermal growth factor receptor inhibitors, and fibroblast growth factor receptor inhibitors, are undergoing clinical trials and are discussed later.

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

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

A Phase II Trial of Dovitinib in BCG-Unresponsive Urothelial Carcinoma with FGFR3 Mutations or Overexpression: Hoosier Cancer Research Network Trial HCRN 12-157

Purpose: To assess the clinical and pharmacodynamic activity of dovitinib in a treatment-resistant, molecularly enriched non-muscle-invasive urothelial carcinoma of the bladder (NMIUC) population.Experimental Design: A multi-site pilot phase II trial was conducted. Key eligibility criteria included the following: Bacillus Calmette-Guerin (BCG)-unresponsive NMIUC (>2 prior intravesical regimens) with increased phosphorylated FGFR3 (pFGFR3) expression by centrally analyzed immunohistochemistry (IHC+) or FGFR3 mutations (Mut+) assessed in a CLIA-licensed laboratory. Patients received oral dovitinib 500 mg daily (5 days on/2 days off). The primary endpoint was 6-month TURBT-confirmed complete response (CR) rate.Results: Between 11/2013 and 10/2014, 13 patients enrolled (10 IHC+ Mut-, 3 IHC+ Mut+). Accrual ended prematurely due to cessation of dovitinib clinical development. Demographics included the following: median age 70 years; 85% male; carcinoma in situ (CIS; 3 patients), Ta/T1 (8 patients), and Ta/T1 + CIS (2 patients); median prior regimens 3. Toxicity was frequent with all patients experiencing at least one grade 3-4 event. Six-month CR rate was 8% (0% in IHC+ Mut-; 33% in IHC+ Mut+). The primary endpoint was not met. Pharmacodynamically active (94-5,812 nmol/L) dovitinib concentrations in urothelial tissue were observed in all evaluable patients. Reductions in pFGFR3 IHC staining were observed post-dovitinib treatment.Conclusions: Dovitinib consistently achieved biologically active concentrations within the urothelium and demonstrated pharmacodynamic pFGFR3 inhibition. These results support systemic administration as a viable approach to clinical trials in patients with NMIUC. Long-term dovitinib administration was not feasible due to frequent toxicity. Absent clinical activity suggests that patient selection by pFGFR3 IHC alone does not enrich for response to FGFR3 kinase inhibitors in urothelial carcinoma. Clin Cancer Res; 23(12); 3003-11. ©2016 AACR.

Targeting fibroblast growth factor receptors and immune checkpoint inhibitors for the treatment of advanced bladder cancer: New direction and New Hope

Bladder cancer is one of the leading causes of death in Europe and the United States. About 25% of patients with bladder cancer have advanced disease (muscle-invasive or metastatic disease) at presentation and are candidates for systemic chemotherapy. In the setting of metastatic disease, use of cisplatin-based regimens improves survival. However, despite initial high response rates, the responses are typically not durable leading to recurrence and death in the vast majority of these patients with median overall survival of 15months and a 5-year survival rate of ⩽10%. Furthermore, unfit patients for cisplatin have no standard of care for first line therapy in advance disease Most second-line chemotherapeutic agents tested have been disappointing. Newer targeted drugs and immunotherapies are being studied in the metastatic setting, their usefulness in the neoadjuvant and adjuvant settings is also an intriguing area of ongoing research. Thus, new treatment strategies are clearly needed. The comprehensive evaluation of multiple molecular pathways characterized by The Cancer Genome Atlas project has shed light on potential therapeutic targets for bladder urothelial carcinomas. We have focused especially on emerging therapies in locally advanced and metastatic urothelial carcinoma with an emphasis on immune checkpoints inhibitors and FGFR targeted therapies, which have shown great promise in early clinical studies.

Effectiveness of capecitabine with or without docetaxel therapy for the treatment of patients with advanced urothelial carcinoma: a single-institution experience

PURPOSE

The purpose of this study was to evaluate the effectiveness and toxicity of capecitabine (C) chemotherapy regimen with or without (w/o) docetaxel (D) in patients with advanced urothelial carcinoma (UC).

RESULTS

Clinical benefit rate were similar in two arms (C arm vs DC arm: 38.9% vs 45.5%, p = 0.411). There were two cases achieved partial response in DC arm. In C arm, the median PFS was 3.0 months (95% CI 2.5-3.5 months) and median OS was 11.3 months (95% CI 8.6-14.1 months). In DC arm, the median PFS was 2.2 months (95% CI 1.7-2.7 months) and median OS was 18 months (95% CI 6.8-29.9 months). Adverse events were mostly acceptable, including myelosuppession, hand-foot syndrome and mucositis. Anemia and leukopenia was found more in the DC arm than in the C arm.

MATERIALS AND METHODS

This is a one-center, observational, retrospective study. From April 2009 to March 2015, a total of 29 patients with metastatic UC were included in the study. Survivals, response rates and toxicities were collected retrospectively.

CONCLUSIONS

The result showed the activity and toxicity of C w/o D. As DC treatment did not reveal better outcome, C or D single-agent might be an option in platinum-failed patients with advanced urothelial carcinoma. Further clinical trials are warranted.

Incorporating VEGF-targeted therapy in advanced urothelial cancer

Patients with relapsed or refractory urothelial carcinoma (UC) have poor prognosis coupled with few options for systemic treatment. The role of angiogenesis in the evolution of cancers has been established, and studies have shown that it plays a key role in the pathogenesis of UC. Many targeted agents have been used in phase I-II trials for the treatment of UC, with encouraging but modest results. Recently, studies combining angiogenesis inhibitors with other chemotherapeutic agents were able to achieve objective responses higher than most commonly used second-line therapies in UC. Future efforts in investigating these therapies in UC rely on identification of biomarkers and other predictors of response to anti-VEGF therapy.

Systemic therapy in muscle-invasive and metastatic bladder cancer: current trends and future promises

Bladder urothelial cancers remain an important urologic cancer with limited treatment options in the locally advanced and metastatic setting. While neoadjuvant chemotherapy for locally advanced muscle-invasive cancers has shown overall survival benefit, clinical uptake in practice have lagged behind. Controversies surrounding adjuvant chemotherapy use are also ongoing. Systemic therapies for metastatic bladder cancer have largely used platinum-based therapies without effective standard second-line therapy options for those who fail, although vinflunine is approved in Europe as a second-line therapy based on a Phase III trial, and most recently, atezolizumab, a checkpoint inhibitor, was approved by the US FDA. Given increasing recognition of mutational signatures expressed in urothelial carcinomas, several promising agents with use of VEGF-targeted therapies, HER2-directed agents and immunotherapies with PD-1/PD-L1 antibodies in various settings are discussed herein.

Obesity and Outcomes in Patients with Metastatic Urothelial Carcinoma

Background: Obesity has been associated with worse outcomes in patients with clinically localized urothelial cancer. However, this impact has not been evaluated in metastatic disease.

Objective: To assess the impact of obesity on outcomes of patients with metastatic urothelial cancer.

Methods: Data from 537 patients were aggregated from eight phase II and phase III clinical trials investigating first-line cisplatin-based combination therapy in metastatic urothelial cancer. Chemotherapy regimen, adverse events, treatment response, and survival outcomes were compared across body mass index (BMI) and body surface area (BSA) categories.

Results: BMI was classified according to WHO criteria (<18.5 underweight, 18.5–24.99 normal weight, 25–29.99 overweight, >30 obese). BSA was classified as either below or greater than or equal to (average for this cohort (1.87 m² for males and 1.66 m² for females). There was no significant difference in number of chemotherapy cycles, adverse events, and response rate or survival outcomes (overall and progression-free) across BMI and BSA categories. There was no significant difference in adverse events across BMI categories, but the incidences of embolic events and renal failure were higher in patients with an average or higher BSA than those with a lower than average BSA (6.6% vs. 3.1% for renal failure p = 0.06; 5.9% vs. 2.7% for renal failure, p = 0.07). There was no significant difference in response rate or survival outcomes (overall and progression-free) amongst BMI and BSA categories.

Conclusions: Obese patients with metastatic urothelial cancer on cisplatin-based therapies have similar response rates, survival outcomes, and tolerability of cisplatin-based therapy to non-obese patients.

Targeting Signaling Transduction Pathways in Bladder Cancer

Systemic therapy for urothelial carcinoma (UC) of the bladder has largely revolved around cytotoxic chemotherapy regimens. However, several recent clinical trials have explored the roles of targeted therapies which specifically inhibit signal transduction pathways. Simultaneously, a rationale for such therapies has come to the forefront of management of this disease because an overabundance of signaling pathways are genetically deranged as a result of point mutation or copy number alteration (CNA) as identified by several recent next generation sequencing (NGS) studies. Importantly, these derangements are found in all stages of disease, and therefore targeted therapies hold promise as a next step in the evolution of the medical management of both localized and metastatic UCC. We review the rationale for and progress in studying inhibition of signal transduction as a means of treatment of UCC.

Targeted Therapy for Metastatic Urothelial Cancer: A Work in Progress

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.A 64-year-old man presented to the clinic to discuss treatment options for progressive metastatic urothelial carcinoma (UC). At age 57 years, he underwent cystoprostatectomy for bacillus Calmette-Guérin-refractory, high-grade noninvasive UC. He was well until age 61 years, when he developed a left upper-tract UC. He underwent left nephroureterectomy, revealing locally advanced high-grade UC invading the renal parenchyma (pT3). Postoperatively, his renal function precluded adjuvant cisplatin-based chemotherapy. He enrolled onto a clinical trial of autologous cellular immunotherapy targeting human epidermal growth factor receptor 2, for which he was eligible on the basis of human epidermal growth factor receptor 2 positivity (≥ 1+ by immunohistochemistry) in his nephrectomy tumor specimen. He was randomly assigned to observation. Two years later, he developed a left pelvic mass. Biopsy confirmed metastatic high-grade UC. He was briefly treated with gemcitabine and carboplatin, but this was discontinued as a result of rapid symptomatic and radiographic progression at 8 weeks. He underwent palliative radiation to the left pelvic mass to relieve symptoms of pain and leg edema and subsequently elected to enroll onto a clinical trial of a programmed death 1 inhibitor. Concurrently, his previously obtained pelvic mass biopsy sample was sent for panel-based genomic profiling. He now returns for his first restaging evaluation. Imaging shows marked progression on study with new metastases to the liver as well as progressive edema and pain in the left leg, limiting ambulation. Review of his now-available genomic testing results reveals alterations in HRAS (G12D) and ATR (S296, Q257). He elected to enroll onto a single-arm, open-label trial of a farnesyl transferase inhibitor for patients with HRAS mutations.

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.

Systemic therapy for metastatic bladder cancer in 2016 and beyond

Metastatic urothelial cancer is generally associated with poor outcomes. In the first-line setting, platinum-based chemotherapy is the standard of care but resistance rapidly develops and the vast majority of patients ultimately experience disease progression. Despite several decades of clinical drug development focused on the treatment of platinum-resistant metastatic urothelial cancer, as of late 2015 there are no standard therapies approved by the US FDA in this setting. However, preliminary results from a series of recent trials exploring innovative approaches forecast a 'sea change' in the management of this difficult to treat malignancy. Herein, we review new approaches for the management of patients with metastatic urothelial cancer focused on three key therapeutic target areas: recurrent somatic alterations, the tumor neovasculature and tumor-associated immune escape.

The safety and efficacy of gemcitabine for the treatment of bladder cancer

Bladder cancer is a common type of cancer with an estimated incidence of more than 70,000 patients and had a mortality of 16,000 patients in the US in 2015. In more than 70% of cases the disease is diagnosed at the non-muscle invasive stage. However, muscle invasive or metastatic stages need multimodal treatment strategies including surgical treatment and chemotherapy in a neoadjuvant, adjuvant or palliative setting. Gemcitabine is a pyrimidine antimetabolite that has shown efficacy when used systemically in bladder cancer with only mild toxicity compared to other chemotherapeutic agents. This article aims to summarize the results of clinical trials in monotherapeutic, combined or sequential treatment strategies, especially considering efficacy and safety of the different therapeutic regimes.

Muscle-invasive urothelial bladder cancer: an update on systemic therapy

Urothelial carcinoma is a common malignancy that carries a poor prognosis when the disease includes muscle invasion. Metastatic urothelial carcinoma is almost uniformly fatal. The evidence behind treatment options in the neoadjuvant, adjuvant and metastatic settings are discussed in this manuscript, with a focused review of standard and investigational cytotoxic, targeted, and immunotherapy approaches. We have focused especially on neoadjuvant cisplatin-based therapy (supported by level one evidence) and on novel immunotherapy agents such as checkpoint inhibitors, which have shown great promise in early clinical studies.

The high incidence of vascular thromboembolic events in patients with metastatic or unresectable urothelial cancer treated with platinum chemotherapy agents

BACKGROUND

The current study compared the incidence of vascular thromboembolic events (VTEs) in patients with metastatic or unresectable urothelial carcinoma (UC) who were treated with gemcitabine and carboplatin (GCb); gemcitabine, carboplatin, and bevacizumab (GCbBev); or gemcitabine and cisplatin (GCis).

METHODS

Patients with UC who were treated with GCbBev on protocol were analyzed prospectively and 2 contemporary control cohorts receiving GCb or GCis were evaluated retrospectively. VTE was defined as either venous or arterial (myocardial infarctions or cerebral vascular accidents) thrombosis. VTEs were considered to be related to treatment if they occurred during treatment or within 4 weeks of the completion of treatment. Associations with chemotherapy regimen were tested using either the Fisher exact test or Kruskal-Wallis test. Clinical factors associated with VTEs were analyzed using conditional logistic regression stratified by treatment regimen.

RESULTS

Among 198 patients, VTEs occurred in 13 of 51 patients treated with GCbBev (26%), 22 of 92 patients treated with GCb (24%), and 8 of 55 patients treated with GCis (15%). Patient characteristics were significantly different between the treatment cohorts in terms of age, prior cystectomy, tumor location near pelvic vessels, Khorana risk group, and receipt of antiplatelet therapy. The incidence of VTE and type of VTE (arterial vs venous) did not differ by type of chemotherapy. Prior cystectomy was associated with an increased risk of VTE (odds ratio, 2.2; 95% confidence interval, 1.0-4.9 [P = .047]).

CONCLUSIONS

The incidence of VTE in Cis-treated patients was similar to prior reports. However, the VTE rate in Cb-treated patients was > 20%, a figure not previously defined in patients with UC and higher than expected. This high incidence of both Cis-related and Cb-related VTEs warrants greater awareness by treating physicians and deserves further study. Cancer 2016;122:712-721. © 2015 American Cancer Society.

Key signaling pathways in the muscle-invasive bladder carcinoma: Clinical markers for disease modeling and optimized treatment

In this review, we evaluate key molecular pathways and markers of muscle-invasive bladder cancer (MIBC). Overexpression and activation of EGFR, p63, and EMT genes are suggestive of basal MIBC subtype generally responsive to chemotherapy. Alterations in PPARγ, ERBB2/3, and FGFR3 gene products and their signaling along with deregulated p53, cytokeratins KRT5/6/14 in combination with the cellular proliferation (Ki-67), and cell cycle markers (p16) indicate the need for more radical treatment protocols. Similarly, the "bell-shape" dynamics of Shh expression levels may suggest aggressive MIBC. A panel of diverse biological markers may be suitable for simulation studies of MIBC and development of an optimized treatment protocol. We conducted a critical evaluation of PubMed/Medline and SciFinder databases related to MIBC covering the period 2009-2015. The free-text search was extended by adding the following keywords and phrases: bladder cancer, metastatic, muscle-invasive, basal, luminal, epithelial-to-mesenchymal transition, cancer stem cell, mutations, immune response, signaling, biological markers, molecular markers, mathematical models, simulation, epigenetics, transmembrane, transcription factor, kinase, predictor, prognosis. The resulting selection of ca 500 abstracts was further analyzed in order to select the latest publications relevant to MIBC molecular markers of immediate clinical significance.

The Impact of Adding Taxanes to Gemcitabine and Platinum Chemotherapy for the First-Line Therapy of Advanced or Metastatic Urothelial Cancer: A Systematic Review and Meta-analysis

CONTEXT

Gemcitabine/platinum chemotherapy is the most widely used first-line regimen for metastatic urothelial carcinoma, and the potential improvement of adding taxanes needs to be clarified.

OBJECTIVE

To study the survival impact of taxane plus gemcitabine/platinum compared with gemcitabine/platinum alone as upfront therapy.

EVIDENCE ACQUISITION

Literature was searched for studies including gemcitabine/platinum ± taxanes (paclitaxel or docetaxel only). We pooled trial level data including the median, proportions, and confidence intervals on response-rate, progression-free survival, overall survival (OS), and side effects. Univariable and multivariable regression models evaluated the prognostic role of addition of taxanes after adjusting for platinum type, performance status 2, and the presence of visceral metastases. Data were weighted by the logarithm of the trial sample size.

EVIDENCE SYNTHESIS

Thirty-five arms of trials including 2,365 patients were selected (seven with taxanes [n=617], and 28 arms without taxanes [n=1,748]). Median OS was univariably significantly different (p=0.019) between trials with and without taxanes. Across trials, the median 'median OS' amongst trials containing taxanes was 15.5 mo, compared with 12.5 mo in trials which did not. Multivariably, visceral disease and performance status were significantly associated with OS, and the addition of taxanes trended toward significantly better OS (p=0.056) and increase in grade ≥ 3 neurotoxicity (p=0.051), regardless of specific platinum agent used.

CONCLUSIONS

In this meta-analysis, adding taxanes to gemcitabine and platinum showed a trend for improved OS and higher grade ≥ 3 neurotoxicity. Improvements in patient selection and the evaluation of a more potent and tolerable tubulin inhibitor in combination with gemcitabine/platinum in a well-powered trial are the critical next steps.

PATIENT SUMMARY

In this report, a trend for improved overall survival and worse neurotoxicity was observed for adding a taxane to first-line gemcitabine/platinum chemotherapy for metastatic urothelial carcinoma. More effective taxanes should be investigated further in urothelial carcinoma in combination with gemcitabine/platinum.

The role of genomics in the management of advanced bladder cancer

OPINION STATEMENT

Advanced bladder cancer (ABC) is an aggressive malignancy with a poor prognosis. For the last 30 years, the standard of care for this disease has consisted of combination chemotherapy with a platinum-containing regimen as first-line therapy. Cisplatin is the most active cytotoxic agent against bladder cancer, but because of competing comorbidities, many patients are ineligible for this agent and instead receive carboplatin. The two-drug regimen of cisplatin and gemcitabine was found to be better tolerated and have comparable efficacy as the four-drug regimen of methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) in a randomized study of patients with advanced disease. Therefore, cisplatin (or carboplatin) and gemcitabine is the most commonly used first-line regimen in this setting. No agents have been approved by the Food and Drug Administration (FDA) for second-line therapy in ABC. If patients are eligible for additional systemic treatment at the time of progression, options include single-agent therapy such as a taxane or pemetrexed, though given the lack of standard approaches participation in a clinical trial should be strongly encouraged. Recent molecular characterization of ABC reveals significant genetic heterogeneity and actionable genomic alterations in the majority of tumors. Emerging therapies may effectively target known molecular drivers of ABC, including the FGFR2, EGFR/HER2, VEGF, MET, and PI3/AKT/mTOR pathways. Reports of dramatic and prolonged responses to targeted therapy provide additional support for the use of genome sequencing in the rationale selection of treatment for subsets of patients. The current focus of clinical trial development is to design molecularly driven studies that "match" tumors with driver mutations and appropriate targeted therapies rather than a "one-size-fits-all" approach based on clinical and pathologic parameters of disease. The hope of patients and clinicians alike is that this therapeutic approach combined with novel agents may usher in a new era of effective treatments for patients with ABC.

Elevating the Horizon: Emerging Molecular and Genomic Targets in the Treatment of Advanced Urothelial Carcinoma

Despite recent advances in the identification of genomic alterations that lead to urothelial oncogenesis in vitro, patients with advanced urothelial carcinomas continue to have poor clinical outcomes. In the present review, we focus on targeted therapies that have yielded the most promising results alone or combined with traditional chemotherapy, including the antiangiogenesis agent bevacizumab, the human epidermal growth factor receptor 2 antibody trastuzumab, and the tyrosine kinase inhibitor cabozantinib. We also describe ongoing and developing clinical trials that use innovative approaches, including dose-dense scheduling of singular chemotherapy combinations, prospective screening of tumor tissues for mutational targets and biomarkers to predict chemosensitivity before the determination of the therapeutic regimen, and novel agents that target proteins in the immune checkpoint regulation pathway (programmed cell death protein 1 [PD-1] and anti-PD-ligand 1) that have shown significant potential in preclinical models and early clinical trials. New agents and targeted therapies, alone or combined with traditional chemotherapy, will only be validated through accrual to developing clinical trials that aim to translate these therapies into individualized treatments and improved survival rates in urothelial carcinoma.

Fatal acute cardiac vasculopathy during cisplatin-gemcitabine-bevacizumab (CGB) chemotherapy for advanced urothelial carcinoma

BACKGROUND

Bladder cancer (BC) accounts for ∼14,680 deaths annually in the U.S. The prognosis of advanced disease remains dismal with current therapies. A phase III intergroup trial for metastatic BC adding bevacizumab to first-line cisplatin-gemcitabine chemotherapy (GCB regimen) is currently ongoing. We report the clinical-pathologic findings of a patient who developed fatal acute cardiac microvascular toxicity while receiving this regimen.

CASE REPORT

A 66 year old man consulted for epigastric pain, nausea, intermittent diarrhea and lightheadedness two weeks after receiving the first cycle of GCB chemotherapy for metastatic BC. Physical evaluation, laboratory studies and electrocardiogram (EKG) were within normal limits except for marked thrombocytopenia that was attributed to his recent chemotherapy. The patient was admitted for observation, rehydrated and started on a proton pump inhibitor. The following day, however, he experienced sudden severe chest and right upper quadrant pain. EKG showed tachycardia, ST elevations in leads V2 and V3, laboratory analyses revealed marked elevation of cardiac troponin I, and an echocardiogram showed a markedly reduced ejection fraction of 10-20%, consistent with rapidly progressive cardiogenic shock. Emergent cardiac catheterization showed no significant coronary artery disease. Sepsis work-up was negative. He became progressively hypotensive, developed multi-organ failure, and died 48 h after admission. Postmortem examination showed diffuse microvasculopathy and changes due to global hypoperfusion of 12-48 h evolution.

CONCLUSIONS

We present the first case of acute, fatal cardiac failure due to microvasculopathy most consistent with bevacizumab-associated toxicity. The findings are discussed in light of the existing literature.

Risk of Vascular Toxicity with Platinum Based Chemotherapy in Elderly Patients with Bladder Cancer

PURPOSE

Platinum based chemotherapy is widely used for bladder cancer but is associated with vascular toxicity, especially thromboembolism. We evaluated the short-term (less than 1 year) and intermediate-term (2 to 5 years) vascular toxicity of platinum agents in older patients with bladder cancer.

MATERIALS AND METHODS

We identified Medicare beneficiaries 66 to 94 years old diagnosed with stage II-III bladder cancer from 1998 to 2007 in the SEER-Medicare database. We measured the association between platinum based chemotherapy and vascular events (thromboembolic and nonthromboembolic) using Cox proportional hazard regression models.

RESULTS

The sample included 5,057 patients, of whom 21.3% received platinum based chemotherapy. Patients receiving platinum based chemotherapy were more likely to be younger and male with less comorbidity than those not receiving any chemotherapy. During the first year after diagnosis the patients who received platinum based chemotherapy had a higher risk of a thromboembolic event (19.8% vs 11.6%, AHR 1.43, 95% CI 1.17-1.75) compared to those who did not receive chemotherapy. The likelihood of having a thromboembolic outcome was similar whether platinum chemotherapy was cisplatin based (21.1%, AHR 1.56, 95% CI 1.22-2.00) or carboplatin based (18.9%, AHR 1.35, 95% CI 1.07-1.71). During years 2 to 5 after diagnosis there was no significant association between platinum chemotherapy and the risk of thromboembolic events. The risk of nonthromboembolic vascular events was not increased with platinum chemotherapy in either period.

CONCLUSIONS

Patients receiving platinum based chemotherapy were at higher risk for thromboembolism but not other vascular events, particularly in the first year after diagnosis. This risk of thromboembolism is similar for cisplatin and carboplatin.

Safety and efficacy of combination therapy with low-dose gemcitabine, paclitaxel, and sorafenib in patients with cisplatin-resistant urothelial cancer

Various regimens including molecular targeted agents have been examined in patients with cisplatin (CDDP)-resistant urothelial cancer (UC). However, some studies have been stopped owing to the development of severe adverse events. The main aim of this study was to examine the anticancer effects, changes in the quality of life (QoL), and safety of combined therapy of low-dose gemcitabine, paclitaxel, and sorafenib (LD-GPS) in patients with CDDP-resistant UC. Twenty patients were treated with gemcitabine (700 mg/m(2) on day 1), paclitaxel (70 mg/m(2) on day 1), and sorafenib (400 mg/day on days 8-22). QoL and pain relief were evaluated using the short-form survey (SF)-36 for bodily pain and the visual analog scale (VAS). VAS scores were significantly decreased by both the second- and third-line therapies (P = 0.012 and 0.028, respectively). The bodily pain score from the SF-36 survey was also significantly (P = 0.012) decreased. Complete responses, partial responses, and stable disease were found in 0 (0.0 %), 1 (5.0 %), and 13 patients (65 %), respectively. The median (interquartile range) period of overall survival after starting of this therapy was 7 (5-11) months. Three patients (15.0 %) stopped therapy because of grade 3 fatigue and hand-foot reactions. LD-GPS therapy was well tolerated by patients with CDDP-resistant UC. QoL was maintained, and improvements in their pain levels were found after treatment; pain relief was detected after third-line therapy. We suggest that this treatment regimen is worthy of consideration as second- and third-line therapy for patients with CDDP-resistant UC.

Conditional Survival in de novo Metastatic Urothelial Carcinoma

Background

Second-line therapy is frequently utilized for metastatic urothelial carcinoma, but there are limited data to guide this approach. While an assessment of overall survival based on registry data may not capture the impact of second- and third-line therapies on clinical outcome, this may be reflected in relative conditional survival (RCS).

Methods

Patients with stage IV urothelial carcinoma diagnosed from 1990–2010 were identified from the Surveillance, Epidemiology and End Results (SEER) dataset. The association of clinicopathologic variables with disease specific survival (DSS) was explored through univariate and multivariate analyses. DSS in subgroups divided by time period (1990–2000 v 2001–2010) was compared using the Kaplan-Meier method and log-rank test. One-year RCS at annual landmarks up to 5 years was compared in subgroups divided by time period.

Results

Of 261,987 patients diagnosed with urothelial carcinoma from 1990–2010, 3,110 patients met criteria for the current analysis. Characteristics of patients diagnosed between 1990 and 2000 (n = 810) and 2001 to 2010 (n = 2,300) were similar and there was no significant difference in DSS between the two groups. On multivariate analysis, older age (age ≥ 80) was associated with shorter DSS (HR 1.79, 95%CI 1.48–2.15), but no association was found between time period of diagnosis and outcome. One-year RCS improved substantially through successive annual landmarks up to 5 years, but no differences were seen in subgroups divided by time of diagnosis.

Conclusions

No difference in RCS was observed amongst patients with stage IV urothelial carcinoma diagnosed from 1990–2000 and 2001–2010. A lack of difference in RCS (more so than cumulative DSS) may reflect a lack of progress in salvage therapies for the disease.

Emerging antibody-based therapeutic strategies for bladder cancer: A systematic review

Bladder cancer is the most common malignancy of the urinary tract, presents the highest recurrence rate among solid tumors and is the second leading cause of death in genitourinary cancers. Despite recent advances in understanding of pathophysiology of the disease, the management of bladder cancer patients remains a clinically challenging problem. Particularly, bladder tumors invading the muscularis propria and disseminated disease are often not responsive to currently available therapeutic approaches, which include surgery and conventional chemotherapy. Antibody-based therapeutic strategies have become an established treatment option for over a decade in several types of cancer. However, bladder cancer has remained mostly an "orphan disease" regarding the introduction of these novel therapeutics, which has been translated in few improvements in patients overall survival. In order to shift this paradigm, several clinical studies involving antibody-based therapeutic strategies targeting the most prominent bladder cancer-related biomolecular pathways and immunological mediators are ongoing. This systematic review explores antibody-based therapeutics for bladder cancer undergoing clinical trial and discusses the future perspectives in this field, envisaging the development of more effective guided therapeutics.

Targeting Hsp90 in urothelial carcinoma

Urothelial carcinoma, or transitional cell carcinoma, is the most common urologic malignancy that carries significant morbidity, mortality, recurrence risk and associated health care costs. Despite use of current chemotherapies and immunotherapies, long-term remission in patients with muscle-invasive or metastatic disease remains low, and disease recurrence is common. The molecular chaperone Heat Shock Protein-90 (Hsp90) may offer an ideal treatment target, as it is a critical signaling hub in urothelial carcinoma pathogenesis and potentiates chemoradiation. Preclinical testing with Hsp90 inhibitors has demonstrated reduced proliferation, enhanced apoptosis and synergism with chemotherapies and radiation. Despite promising preclinical data, clinical trials utilizing Hsp90 inhibitors for other malignancies had modest efficacy. Therefore, we propose that Hsp90 inhibition would best serve as an adjuvant treatment in advanced muscle-invasive or metastatic bladder cancers to potentiate other therapies. An overview of bladder cancer biology, current treatments, molecular targeted therapies, and the role for Hsp90 inhibitors in the treatment of urothelial carcinoma is the focus of this review.

Molecular biology and targeted therapies for urothelial carcinoma

Metastatic urothelial cancer (UC) is associated with poor prognosis. In the first-line setting, platinum-based chemotherapy is the standard of care but resistance rapidly occurs. With no validated treatment proven to increase survival after platinum failure, there is an urgent unmet medical need to develop new and efficacious cytotoxic agents. A better understanding of the molecular signaling pathways regulating UC has led to the development of new and innovative therapeutic strategies. Despite this, many recent drugs show only modest activity as single agents, and combining them with standard chemotherapy does not seem to enhance efficacy. Ongoing research is producing, however, a generation of new drugs that are showing promising results in clinical trials. This paper aims to review the most important mechanisms in bladder cancer tumorigenesis and describe the new therapeutic options currently undergoing evaluation in clinical trials.

Targeted therapy in advanced bladder cancer: what have we learned?

Despite advances in the treatment of other genitourinary malignancies, no novel therapies have been approved by the US Food and Drug Administration for urothelial carcinoma (UC) in the last 20 years. To date, no clinical trials of targeted agents in UC have led to improvements in survival compared with cytotoxic therapy. This article outlines representative trials of targeted therapies in UC and discusses the significance of genetic preselection in trial design as a method to optimize responses to these agents, thus, hopefully expanding the armamentarium of treatment options against this lethal disease.

Optimal treatment for metastatic bladder cancer

Metastatic bladder cancer is a lethal disease. Cisplatin-based chemotherapy, including the combination regimens gemcitabine-cisplatin and methotrexate-vinblastine-doxorubicin-cisplatin, are the standard first-line therapies. Second-line therapies have modest activity and no significant improvement in patient outcomes. Agents targeting growth, survival, and proliferation pathways have been added to cytotoxic therapy with limited added benefit to date. Modulating host immune response to cancer-associated antigens appears promising, with multiple new therapeutic approaches being pursued. Next-generation sequencing of invasive urothelial carcinoma has provided insights into the biology of this disease and potential actionable targets. Alterations in the receptor tyrosine kinase/Ras pathway and the phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin pathway represent potential therapeutic targets in advanced disease, and novel agents are in development. Recent data from the Cancer Genome Atlas Research Network bladder cancer cohort and other efforts suggest that mutations in chromatin-regulatory genes are very common in invasive bladder tumors, and are more frequent than in other studied tumors. The discovery of new genomic alterations challenges drug development to change the course of this disease.

Future directions and targeted therapies in bladder cancer

There are substantial unmet needs for patients with metastatic urothelial carcinoma (UC). First-line cisplatin-based chemotherapy regimens yield a median survival of 12 to 15 months and long-term survival in 5% to 15%. Salvage systemic therapy yields a median survival of 6 to 8 months. Hence, the discovery of novel therapeutic targets is of paramount importance. Recent molecular analyses have provided insights regarding molecular tumor tissue alterations on multiple platforms. A multidisciplinary effort using innovative clinical trial designs and exploiting preclinical signals of robust activity guided by predictive biomarkers may provide much needed clinical advances in therapy for advanced UC.

Recurrent hematuria in a patient with a previously undiagnosed transitional cell carcinoma of the right ureter after intravitreal bevacizumab (Avastin) injection: a case report

PURPOSE

To report a case of gross hematuria in a patient with previously undiagnosed urothelial carcinoma of the right ureter after intravitreal bevacizumab (Avastin) injections.

METHODS

In this case report and review of the literature, an 81-year-old woman presented with neovascular age-related macular degeneration in the left eye. She was treated with repeated intravitreal bevacizumab (Avastin) injections. After injection, she reported two episodes of gross hematuria. After disclosing this information to her ophthalmologist, bevacizumab treatment was suspended and the hematuria resolved. Urological evaluation revealed no abnormalities. Approximately 1 year later, treatment with intravitreal bevacizumab was resumed. After three injections, she again reported gross hematuria. Urological evaluation at that time revealed a high-grade urothelial carcinoma of the right ureter. A right nephroureterectomy was performed, and bevacizumab treatment was resumed. She did not report any subsequent episodes of hematuria.

CONCLUSION

Hematuria has previously been reported with systemic administration of bevacizumab. However, hematuria after intravitreal injections of bevacizumab has not been reported and is most likely occurring as a result of the systemic absorption of the drug. Further investigation of the systemic effects of intravitreal bevacizumab may be warranted.

Dovitinib: rationale, preclinical and early clinical data in urothelial carcinoma of the bladder

INTRODUCTION

Bladder cancer (BC) is the third and fifth cancer in men in terms of incidence and mortality in the US. Overexpression and mutations of fibroblast growth factor receptor 3 (FGFR3) are frequently found in BC and can represent a very interesting therapeutic target. Different FGFR3-targeted strategies have been investigated through in vitro and in vivo settings, including FGFR3 tyrosine kinase inhibitors such as dovitinib .

AREAS COVERED

The authors review the data that provide a scientific rationale for FGFR3-targeted therapy in BC. They also provide an evaluation of the currently available in vitro and in vivo data on the use of dovitinib in BC patients.

EXPERT OPINION

The development and progression of BC rely on a very complex signaling network that involves many different receptors aside from FGFR3 and VEGFR2. The involved signaling network can also be very different from one BC to the other, and can also evolve through time in the same patient. Inhibiting only one single target may thus not be sufficient to achieve a complete downstream oncogenic signaling blockage. Additionally, in vitro data on the use of neutralizing monoclonal antibodies targeting FGFR3 show that it can be a more efficient strategy to reach the same goal, with the potential advantage of less toxicity.

Systemic therapy for bladder cancer - a medical oncologist's perspective

Advanced bladder cancer, both muscle-invasive localized disease and metastatic disease, is managed with systemic chemotherapy. Cisplatin-based multi-agent chemotherapy remains the cornerstone for systemic therapy. MVAC (methotrexate-vinblastine-doxorubicin-cisplatin) has been most rigorously studied, both neoadjuvantly and for palliation of metastatic disease. For metastatic disease, cisplatin-gemcitabine (GC) has compared favorably to MVAC due to improved tolerability with similar efficacy. GC has been adopted as standard therapy. Neoadjuvant chemotherapy for muscle-invasive bladder cancer improves survival among those patients eligible to receive cisplatin. Adjuvant chemotherapy is difficult to administer effectively given morbidity of radical cystectomy, and studies have shown mixed results about its benefit. Non-cisplatin regimens have been investigated but remain experimental and reserved for those not candidates for cisplatin in the metastatic setting. While multiple agents have been studied after metastatic disease progression after cisplatin-based therapy, there remain no FDA-approved therapies for the second line. Future trials with anti-VEGF therapy and immunotherapy are actively being investigated. This review examines the systemic therapy available to oncologists with current evidence and future directions.

A randomized phase 2 trial of gemcitabine/cisplatin with or without cetuximab in patients with advanced urothelial carcinoma

BACKGROUND

Epidermal growth factor receptor overexpression is associated with poor outcomes in urothelial carcinoma (UC). Cetuximab (CTX) exhibited an antitumor effect in in vivo UC models. The efficacy of gemcitabine/cisplatin (GC) with or without CTX in patients with advanced UC was evaluated.

METHODS

Patients with advanced UC, measurable disease, and adequate organ function were randomized 1:2 to cisplatin (70 mg/m(2) ) on day 1 plus gemcitabine (1000 mg/m(2) ) on days 1, 8, and 15 (arm A) or GC plus CTX (500 mg/m(2) ) on days 1 and 15 (arm B). The primary endpoint was the overall response rate. The secondary endpoints were the response duration, safety, progression-free survival, overall survival, determination of whether or not CTX sensitized nonresponders to GC, and exploratory biomarker analysis. The accrual targets were 27 and 54 patients for the 2 arms, respectively. The overall response rate was reported by arm with binomial confidence intervals (CIs). Kaplan-Meier methods were used for time-to-event endpoints.

RESULTS

Eighty-eight eligible patients were randomized; 87 were toxicity-evaluable, and 85 were response-evaluable. The overall response rates were 57.1% for arm A (95% CI = 37%-76%) and 61.4% for arm B (95% CI = 48%-74%). The median progression-free survival times were 8.5 months for arm A (95% CI = 5.7-10.4 months) and 7.6 months for arm B (95% CI = 6.1-8.7 months). The median overall survival times were 17.4 months for arm A (95% CI = 12.8 months to unreached) and 14.3 months for arm B (95% CI = 11.6-22.2 months). The most common grade 3/grade 4 adverse events in both arms were myelosuppression and nausea. Thromboembolism, acneiform rash, fatigue, pain, hypersensitivity reactions, elevated transaminases, hyponatremia, and hypomagnesemia were more common in arm B; 3 grade 5 adverse events occurred in arm B. The presence of primary disease significantly correlated with thromboembolism. An increased soluble E-cadherin level after cycle 2 correlated with a higher risk of death.

CONCLUSIONS

GC plus CTX was feasible but was associated with more adverse events and no improvements in outcomes.

Targeted therapies in urothelial carcinoma

PURPOSE OF REVIEW

Greater understanding of the biology and genetics of urothelial carcinoma is helping to identify and define the role of molecules and pathways appropriate for novel-targeted therapies. Here, we review the targeted therapies that have been reported or are in ongoing urothelial carcinoma clinical trials, and highlight molecular targets characterized in preclinical and clinical studies.

RECENT FINDINGS

Trials in nonmuscle-invasive bladder cancer are evaluating the role of immunotherapy and agents targeting vascular endothelial growth factor (VEGF) or fibroblast growth factor receptor-3. In muscle-invasive bladder cancer, neoadjuvant studies have focused on combining VEGF agents with chemotherapy; adjuvant studies are testing vaccines and agents targeting the human epidermal growth factor receptor 2, p53, and Hsp27. In the first-line treatment of metastatic urothelial carcinoma, tubulin, cytotoxic T-lymphocyte antigen 4, Hsp27, and p53 are novel targets in clinical trials. The majority of targeted agents studied in urothelial carcinoma are in the second-line setting; new targets include CD105, polo-like kinase-1, phosphatidylinositide 3-kinases (PI3K), transforming growth factor β receptor/activin receptor-like kinase β, estrogen receptor, and the hepatocyte growth factor receptor (HGFR or MET).

SUMMARY

Development of targeted therapies for urothelial carcinoma is still in early stages, consequently there have been no major therapeutic advances to date. However, greater understanding of urothelial carcinoma and solid tumor biology has resulted in a proliferation of clinical trials that could lead to significant advances in treatment strategies.