Consensus statement on best practice management regarding the use of intravesical immunotherapy with BCG for bladder cancer

Society for Immunotherapy of Cancer consensus statement on immunotherapy for the treatment of bladder carcinoma

The standard of care for most patients with non-muscle-invasive bladder cancer (NMIBC) is immunotherapy with intravesical Bacillus Calmette-Guérin (BCG), which activates the immune system to recognize and destroy malignant cells and has demonstrated durable clinical benefit. Urologic best-practice guidelines and consensus reports have been developed and strengthened based on data on the timing, dose, and duration of therapy from randomized clinical trials, as well as by critical evaluation of criteria for progression. However, these reports have not penetrated the community, and many patients do not receive appropriate therapy. Additionally, several immune checkpoint inhibitors have recently been approved for treatment of metastatic disease. The approval of immune checkpoint blockade for patients with platinum-resistant or -ineligible metastatic bladder cancer has led to considerations of expanded use for both advanced and, potentially, localized disease. To address these issues and others surrounding the appropriate use of immunotherapy for the treatment of bladder cancer, the Society for Immunotherapy of Cancer (SITC) convened a Task Force of experts, including physicians, patient advocates, and nurses, to address issues related to patient selection, toxicity management, clinical endpoints, as well as the combination and sequencing of therapies. Following the standard approach established by the Society for other cancers, a systematic literature review and analysis of data, combined with consensus voting was used to generate guidelines. Here, we provide a consensus statement for the use of immunotherapy in patients with bladder cancer, with plans to update these recommendations as the field progresses.

Safe and effective administration of BCG for bladder carcinoma in situ after umbilical cord blood stem cell transplantation

Although intravesical Bacillus Calmette-Guérin (BCG) instillation is the standard treatment for carcinoma in situ of the bladder, it is generally contraindicated in immunocompromised patients. Here we report the first case, to our knowledge, of BCG treatment for a bladder cancer patient who had received umbilical cord blood stem cell transplantation (UCBSCT). BCG can be given safely and effectively in select cases where reconstitution of the immune system has been achieved at least 2 years after UCBSCT.

The Antineoplastic Activity of Photothermal Ablative Therapy with Targeted Gold Nanorods in an Orthotopic Urinary Bladder Cancer Model

BACKGROUND

Gold nanoparticles treated with near infrared (NIR) light can be heated preferentially, allowing for thermal ablation of targeted cells. The use of novel intravesical nanoparticle-directed therapy in conjunction with laser irradiation via a fiber optic cystoscope, represents a potential ablative treatment approach in patients with superficial bladder cancer.

OBJECTIVE

To examine the thermal ablative effect of epidermal growth factor receptor (EGFR)-directed gold nanorods irradiated with NIR light in an orthotopic urinary bladder cancer model.

METHODS

Gold nanorods linked to an anti-EGFR antibody (Conjugated gold NanoRods - CNR) were instilled into the bladder cavity of an orthotopic murine xenograft model with T24 bladder cancer cells expressing luciferase. NIR light was externally administered via an 808 nm diode laser. This treatment was repeated weekly for 4 weeks. The anti-cancer effect was monitored by an in vivo imaging system in a non-invasive manner, which was the primary outcome of our study.

RESULTS

The optimal approach for an individual treatment was 2.1 W/cm² laser power for 30 seconds. Using this in vivo model, NIR light combined with CNR demonstrated a statistically significant reduction in tumor-associated bioluminescent activity (n = 16) compared to mice treated with laser alone (n = 14) at the end of the study (p = 0.035). Furthermore, the CNR+NIR light treatment significantly abrogated bioluminescence signals over a 6-week observation period, compared to pre-treatment levels (p = 0.045).

CONCLUSIONS

Photothermal tumor ablation with EGFR-directed gold nanorods and NIR light proved effective and well tolerated in a murine in vivo model of urinary bladder cancer.

Intravesical bacillus Calmette-Guérin instillation in non-muscle-invasive bladder cancer: A review

Intravesical bacillus Calmette-Guérin has been the standard of care for high-risk non-muscle-invasive bladder cancer for 40 years. It remains one of the most successful immunotherapies ever used. Bacillus Calmette-Guérin shows superior efficacy to alternative intravesical treatments, and has an established role in reducing both recurrence and progression in non-muscle-invasive bladder cancer. It remains relatively safe, and has acceptable tolerability of both local and systemic side-effects. The present review provides insights into the role of bacillus Calmette-Guérin compared with alternative treatments both in primary and refractory settings.

Combination of Plant Virus Nanoparticle-Based in Situ Vaccination with Chemotherapy Potentiates Antitumor Response

Immunotherapeutics are gaining more traction in the armamentarium used to combat cancer. Specifically, in situ vaccination strategies have gained interest because of their ability to alter the tumor microenvironment to an antitumor state. Herein, we investigate whether flexuous plant virus-based nanoparticles formed by the potato virus X (PVX) can be used as an immunotherapeutic for in situ vaccine monotherapy. We further developed dual chemo-immunotherapeutics by incorporating doxorubicin (DOX) into PVX yielding a dual-functional nanoparticle (PVX-DOX) or by coadministration of the two therapeutic regimes, PVX immunotherapy and DOX chemotherapy (PVX+DOX). In the context of B16F10 melanoma, PVX was able to elicit delayed tumor progression when administered as an intratumoral in situ vaccine. Furthermore, the coadministration of DOX via PVX+DOX enhanced the response of the PVX monotherapy through increased survival, which was also represented in the enhanced antitumor cytokine/chemokine profile stimulated by PVX+DOX when compared to PVX or DOX alone. Importantly, coadministered PVX+DOX was better for in situ vaccination than PVX loaded with DOX (PVX-DOX). Whereas the nanomedicine field strives to design multifunctional nanoparticles that integrate several functions and therapeutic regimens into a single nanoparticle, our data suggest a paradigm shift; some therapeutics may need to be administered separately to synergize and achieve the most potent therapeutic outcome. Altogether, our studies show that development of plant viral nanoparticles for in situ vaccines for treatment is a possibility, and dual mechanistic therapeutics can increase efficacy. Nonetheless, combining immunotherapeutics with cytolytic chemotherapy requires detailed investigation to inform optimal integration of cytolytic and immunotherapies and maximize synergy and efficacy.

Plant viruses and bacteriophages for drug delivery in medicine and biotechnology

There are a wide variety of synthetic and naturally occurring nanomaterials under development for nanoscale cargo-delivery applications. Viruses play a special role in these developments, because they can be regarded as naturally occurring nanomaterials evolved to package and deliver cargos. While any nanomaterial has its advantage and disadvantages, viral nanoparticles (VNPs), in particular the ones derived from plant viruses and bacteriophages, are attractive options for cargo-delivery as they are biocompatible, biodegradable, and non-infectious to mammals. Their protein-based structures are often understood at atomic resolution and are amenable to modification with atomic-level precision through chemical and genetic engineering. Here we present a focused review of the emerging technology development of plant viruses and bacteriophages targeting human health and agricultural applications. Key target areas of development are their use in chemotherapy, photodynamic therapy, pesticide-delivery, gene therapy, vaccine carriers, and immunotherapy.

What is new in non-muscle-invasive bladder cancer in 2016?

Approximately 75% of bladder cancers are non-muscle-invasive bladder cancer (NMIBC), and 50% of NMIBC patients who are treated with transurethral resection (TUR) have a recurrence of the disease and 5-25% of these patients progressed to muscle-invasive disease after repeated recurrences. NMIBC patients receive various treatments aimed at reducing disease recurrence and progression. Although the recurrence rate of disease remains above target, thus increasing treatment cost, the true rate of recurrence after the primary surgery is controversial. Recurrences can be categorized as either true recurrence due to aggressive tumor biology and implantation of floating cancer cells or false recurrence such as small, flat, or carcinoma in situ lesions overlooked in the primary procedure. Here we discuss new diagnostic methods and treatment options to improve outcomes and reduce recurrence rates in NMIBC.

Blebbishields and mitotic cells exhibit robust macropinocytosis

Cancer stem cells can survive and undergo transformation after apoptosis by initiating robust endocytosis. Endocytosis in-turn drives formation of serpentine filopodia, which promote construction of blebbishields from apoptotic bodies. However, the status and role of macropinocytosis in blebbishields is not known. Here, we show by scanning electron microscopy and by macropinocytosis assays that blebbishields exhibit robust macropinocytosis. Inhibiting dynamin-mediated endocytosis does not affect macropinocytosis in blebbishields or in mitotic cells. In addition, inhibiting macropinocytosis did not inhibit construction of blebbishields from apoptotic bodies. Thus, although apoptotic cancer stem cells exhibit robust macropinocytosis, macropinocytosis is not essential to generate blebbishields, although it may play other roles in blebbishield biology. © 2016 BioFactors, 43(2):181-186, 2017.

Bladder cancer

Bladder cancer is a complex disease associated with high morbidity and mortality rates if not treated optimally. Awareness of haematuria as the major presenting symptom is paramount, and early diagnosis with individualised treatment and follow-up is the key to a successful outcome. For non-muscle-invasive bladder cancer, the mainstay of treatment is complete resection of the tumour followed by induction and maintenance immunotherapy with intravesical BCG vaccine or intravesical chemotherapy. For muscle-invasive bladder cancer, multimodal treatment involving radical cystectomy with neoadjuvant chemotherapy offers the best chance for cure. Selected patients with muscle-invasive tumours can be offered bladder-sparing trimodality treatment consisting of transurethral resection with chemoradiation. Advanced disease is best treated with systemic cisplatin-based chemotherapy; immunotherapy is emerging as a viable salvage treatment for patients in whom first-line chemotherapy cannot control the disease. Developments in the past 2 years have shed light on genetic subtypes of bladder cancer that might differ from one another in response to various treatments.

Immunological mechanisms of intravesical chitosan/interleukin-12 immunotherapy against murine bladder cancer

There is a critical unmet clinical need for bladder cancer immunotherapies capable of inducing durable antitumor immunity. We have shown that four intravesical treatments with a simple co-formulation of interleukin-12 and the biopolymer chitosan not only destroy orthotopic bladder tumors, but also promote a potent long-lasting systemic immune response as evidenced through tumor-specific in vitro killing assays, complete protection from rechallenge, and abscopal antitumor responses at distant non-treated tumors. This study investigates the immunological kinetics underlying these results. We show through depletion studies that CD8⁺ T cells are required for initial tumor rejection, but CD4⁺ T cells protect against rechallenge. We also show that even a single intravesical treatment can eliminate tumors in 50% of mice with 6/9 and 7/8 mice eliminating tumors after three or four treatments respectively. We then performed immunophenotyping studies to analyze shifts in immune cell populations after each treatment within the tumor itself as well as in secondary lymphoid organs. These studies demonstrated an initial infiltration of macrophages and granulocytes followed by increased CD4⁺ and CD8⁺ effector-memory cells. This was coupled with a decreased level of regulatory T cells in peripheral lymph nodes as well as decreased myeloid-derived suppressor cell infiltration in the bladder. Taken together, these data demonstrate the ability of properly delivered interleukin-12-based therapies to engage adaptive immunity within the tumor itself as well as throughout the body and strengthen the case for clinical translation of chitosan/interleukin-12 as an intravesical treatment for bladder cancer.

Immunogenic Human Papillomavirus Pseudovirus-Mediated Suicide-Gene Therapy for Bladder Cancer

Bladder cancer is the second most common urological malignancy in the world. In 70% of cases it is initially diagnosed as non-muscle-invasive bladder cancer (NMIBC) and it is amenable to local treatments, with intravesical (IVES) Bacillus-Calmette-Guerin (BCG) immunotherapy being routinely used after transurethral resection of the lesion. However, this treatment is associated with significant side-effects and treatment failures, highlighting the necessity of novel strategies. One potent approach is the suicide-gene mediated therapy/prodrug combination, provided tumor-specificity can be ensured and anti-tumor immune responses induced. Using the mouse syngeneic orthotopic MB49-bladder tumor model, here we show that IVES human papillomavirus non-replicative pseudovirions (PsV) can pseudoinfect tumors with a ten-fold higher efficacy than normal bladders. In addition, PsV carrying the suicide-gene herpes-simplex virus thymidine kinase (PsV-TK) combined to Ganciclovir (GCV) led to immunogenic cell-death of tumor cells in vitro and to MB49-specific CD8 T-cells in vivo. This was associated with reduction in bladder-tumor growth and increased mice survival. Altogether, our data show that IVES PsV-TK/GCV may be a promising alternative or combinatory treatment for NMIBC.

Natural biology and management of nonmuscle invasive bladder cancer

PURPOSE OF REVIEW

This article reviews the natural biology of noninvasive bladder cancer and its management strategies while summarizing the most recent advances in the field.

RECENT FINDINGS

Nonmuscle invasive bladder cancer (NMIBC) has a tendency to recur and progress. Risk stratification has helped triage patients but improved tools, including biomarkers, are still needed. Enhanced endoscopy with photodynamic imaging, narrow band imaging, optical coherence tomography and confocal laser endomicroscopy show promise for diagnosis, risk stratification and disease monitoring. Attempts at better treatment, especially in refractory high-risk cases, include the addition of intravesical hyperthermia, combination and sequential therapy with existing agents and the use of novel agents such as mycobacterial cell wall extract. New data are emerging regarding the potential role of active surveillance in low-risk patients.

SUMMARY

NMIBC represents a variety of disease states and continues to pose management challenges. As our understanding of tumor biology improves and technology advances, achieving better outcomes through individualized care may be possible.

Papillary Recurrence of Bladder Cancer at First Evaluation after Induction Bacillus Calmette-Guérin Therapy: Implication for Clinical Trial Design

BACKGROUND

Recurrence with papillary tumor(s) by 3-mo after induction bacillus Calmette-Guérin (BCG) is historically believed to be a poor prognostic indicator in patients with high-risk non-muscle invasive bladder cancer. However, the impact of a clinical Ta (cTa) papillary recurrence at 3 mo after BCG is often debated.

OBJECTIVE

To evaluate the prognostic implications of cTa papillary recurrence found 3 mo after induction BCG therapy and to evaluate its significance in clinical trial design.

DESIGN, SETTING, AND PARTICIPANTS

We reviewed our database of 917 patients who underwent transurethral resection and induction of BCG from 1995 to 2012. Clinical characteristics were compared between 3-mo recurrence stages.

INTERVENTION

Transurethral resection of bladder tumor and intravesical therapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Chi-square analysis and Student t test were used to compare clinical characteristics between 3-mo recurrence stages. Kaplan-Meier method was used to determine bladder-preservation time, progression-free survival, and disease-specific survival.

RESULTS AND LIMITATIONS

We identified 84 patients who met the study criteria (66 patients with cTa and 18 patients with clinical T1 [cT1]). The median follow-up for the entire cohort was 74 mo. Of the patients with cTa recurrence, 60 continued with bladder-sparing therapy. Patients with a high-grade cTa recurrence who continued bladder-sparing therapy had a 17% incidence of disease progression and a 62% incidence of recurrence within 1 yr. No patients with low-grade cTa recurrence (n=13) developed disease progression or underwent radical cystectomy. Patients with an initial cTa at diagnosis had a higher 5-yr bladder preservation rate than those with an initial cT1 diagnosis (84% vs 61%; p=0.041). Patients with high-grade cTa recurrence and those with cT1 recurrence had similar outcomes with respect to death rates over the entire follow-up period (11% and 15%, respectively), as well as 5-yr progression-free survival (77% vs 83%). Limitations include using a single institution and a retrospective review.

CONCLUSIONS

Patients with low-grade cTa papillary recurrence 3 mo after induction of BCG can safely continue with bladder-sparing therapy. Patients with high-grade cTa papillary recurrence at that time have risks of recurrence and progression similar to those of patients with cT1 recurrence. These are important factors to consider during clinical trial design.

PATIENT SUMMARY

Low-grade clinical Ta papillary recurrence following induction of bacillus Calmette-Guérin therapy can be safely managed conservatively, although a high-grade clinical Ta recurrence should be treated similar to a clinical T1 recurrence due to its comparable progression rates.

Intravesical and alternative bladder-preservation therapies in the management of non-muscle-invasive bladder cancer unresponsive to bacillus Calmette-Guérin

Intravesical Bacillus Calmette-Guérin (BCG) remains the standard of care in the treatment of bladder carcinoma in situ and as adjuvant therapy after thorough transurethral resection of high-grade non-muscle-invasive bladder cancer. Despite BCG therapy, in up to 40% of patients it would recur and 60% to 70% of those would fail repeat BCG induction be deemed BCG unresponsive. For such patients, cystectomy remains the preferred treatment option per the American Urological Association and European Association of Urology, though some patients would be medically unfit or refuse radical surgery. Further intravesical therapy for bladder-preservation therapies may preserve quality of life in these patients and in some cases can be curative. There are numerous non-BCG intravesical salvage options available, including immunotherapy, single-agent chemotherapy, combination chemotherapy, and device-assisted chemotherapy. In addition, investigation of radiation-based treatment and other novel therapies including checkpoint inhibitors (programmed death-1/programmed death ligand-1), are currently underway. In this review, we examine the current status of alternatives to BCG in salvage therapy for bladder preservation.

Cytokine Panel for Response to Intravesical Therapy (CyPRIT): Nomogram of Changes in Urinary Cytokine Levels Predicts Patient Response to Bacillus Calmette-Guérin

The response of non-muscle-invasive bladder cancer (NMIBC) to intravesical immunotherapy with bacillus Calmette-Guérin (BCG) depends on adequate stimulation of an immune response. Although BCG has been used for decades, we lack tools to accurately predict response in individual patients. To address this deficiency, we initiated a clinical trial in patients with intermediate- and high-risk NMIBC. BCG was administered according to the Southwest Oncology Group protocol. Urine samples were collected for cytokine assay at baseline, immediately before and after BCG instillation at 6 wk, and immediately before and after the third BCG instillation of the first maintenance course. Levels of 12 cytokines were measured, and changes from baseline were calculated after treatment. A total of 130 patients were enrolled. Increases in single cytokines correlated with recurrence, but the best predictor of recurrence was changes in a combination of cytokines. A nomogram (CyPRIT) constructed using urinary levels of nine inducible cytokines (IL-2, IL-6, IL-8, IL-18, IL-1ra, TRAIL, IFN-γ, IL-12[p70], and TNF-α) predicted the likelihood of recurrence with 85.5% accuracy (95% confidence interval 77.9–93.1%).” This cytokine panel and nomogram have potential for identifying patients at risk of tumor recurrence during BCG treatment to guide modification of the dose and duration of BCG immunotherapy.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01007058.

Immunotherapy and Radiation - A New Combined Treatment Approach for Bladder Cancer?

Recently, immunotherapy with checkpoint inhibitors has been showing promise in clinical trials for stage IV bladder cancer. Herein, we review the literature regarding the role for radiation therapy, the role for immunotherapy, and the potential synergy of these treatments combined in bladder cancer. There is ample pre-clinical data in a number of different tumor models, coupled with a growing body of clinical evidence in melanoma and other malignancies to suggest combining radiation and immunotherapy could lead to substantial advances in treatment outcomes for bladder cancer. Yet, these data for bladder cancer remain at the pre-clinical stage, and further study is needed.