Lifestyle and Non-muscle Invasive Bladder Cancer Recurrence, Progression, and Mortality: Available Research and Future Directions

Microbiome and bladder cancer: the role of probiotics in treatment

Bladder cancer (BCa) remains a significant global health challenge, with increasing interest in the role of the bladder microbiome in its pathogenesis, progression and treatment outcomes. The complex relationship between bladder cancer and the microbiome, as well as the potential impact of probiotics on treatment effectiveness, is currently under investigation. Research suggests that the microbiota may influence BCa recurrence prevention and enhance the efficacy of the Bacillus Calmette-Guérin (BCG) vaccine. Recent studies reveal differences in the bladder microbiome between individuals without bladder cancer and those with the disease. In the healthy bladder, Streptococcus and Lactobacillus are consistently identified as the most prevalent genera. However, in men, the predominant bacterial genera are Staphylococcus, Corynebacterium and Streptococcus, while in women with bladder cancer, Gardnerella and Lactobacillus are dominant. Probiotics, particularly Lactobacillus spp., can exhibit anti-tumor properties by competing with pathogenic strains involved in carcinogenesis or by producing regulatory substances. They regulate cancer signaling, induce apoptosis, inhibit mutagenic activity, downregulate oncogene expression, induce autophagy, inhibit kinases, reactivate tumor suppressors and prevent metastasis. These mechanisms have shown promising results in both preclinical and some clinical studies.

Deciphering the molecular heterogeneity of intermediate- and (very-)high-risk non-muscle-invasive bladder cancer using multi-layered -omics studies

Bladder cancer (BC) is the most common malignancy of the urinary tract. About 75% of all BC patients present with non-muscle-invasive BC (NMIBC), of which up to 70% will recur, and 15% will progress in stage and grade. As the recurrence and progression rates of NMIBC are strongly associated with some clinical and pathological factors, several risk stratification models have been developed to individually predict the short- and long-term risks of disease recurrence and progression. The NMIBC patients are stratified into four risk groups as low-, intermediate-, high-risk, and very high-risk by the European Association of Urology (EAU). Significant heterogeneity in terms of oncological outcomes and prognosis has been observed among NMIBC patients within the same EAU risk group, which has been partly attributed to the intrinsic heterogeneity of BC at the molecular level. Currently, we have a poor understanding of how to distinguish intermediate- and (very-)high-risk NMIBC with poor outcomes from those with a more benign disease course and lack predictive/prognostic tools that can specifically stratify them according to their pathologic and molecular properties. There is an unmet need for developing a more accurate scoring system that considers the treatment they receive after TURBT to enable their better stratification for further follow-up regimens and treatment selection, based also on a better response prediction to the treatment. Based on these facts, by employing a multi-layered -omics (namely, genomics, epigenetics, transcriptomics, proteomics, lipidomics, metabolomics) and immunohistopathology approach, we hypothesize to decipher molecular heterogeneity of intermediate- and (very-)high-risk NMIBC and to better stratify the patients with this disease. A combination of different -omics will provide a more detailed and multi-dimensional characterization of the tumor and represent the broad spectrum of NMIBC phenotypes, which will help to decipher the molecular heterogeneity of intermediate- and (very-)high-risk NMIBC. We think that this combinatorial multi-omics approach has the potential to improve the prediction of recurrence and progression with higher precision and to develop a molecular feature-based algorithm for stratifying the patients properly and guiding their therapeutic interventions in a personalized manner.

Prediction of recurrence risk in patients with non-muscle-invasive bladder cancer

Objective

Non-muscle-invasive bladder cancer (NMIBC) remains a common challenge in uro-oncology with conflicting reports on recurrence risk. This study aimed to elucidate the recurrence rate of NMIBC in the Cancer Clinic of Shahid Beheshti Hospital in Iran and to investigate related parameters affecting recurrence risk.

Methods

The data of 143 patients with NMIBC, who underwent treatment between January 2017 and January 2020 and were followed up from the initial transurethral resection of bladder tumor until November 30, 2020 in our institution, were retrospectively assessed. The Cox regression analysis and Kaplan-Meier plot of recurrence-free survival were used to determine independent contributing factors for tumor recurrence.

Results

Among patients with NMIBC, 83.9% were male, and 16.1% were female, with a mean age of 64.4 (standard deviation [SD] 12.9) years. During the follow-up, 71 (49.7%) patients showed tumor recurrence, with a mean recurrence time of 11.5 (SD 6.9) months. In the Chi-square test or Fisher's exact test, the age (≥65 years) (p=0.037), obesity (body mass index ≥30 kg/m2) (p=0.004), no diabetes mellitus (p=0.005), smoking (current or former smoker) (p=0.001), immediate perfusion therapy (p=0.035), number of tumors (>3) (p<0.001), and tumor stage (Ta, T1, and Tis) (p=0.001) had independent significant effects on the recurrence of NMIBC. The multivariate Cox regression analysis indicated that preoperative obesity (hazards ratio [HR] 7.90; 95% confidential interval [CI] 4.01-15.55; p<0.001), current or former smoking (HR 1.85; 95% CI 1.07-3.20; p=0.027), and a high-grade tumor (HR 4.03; 95% CI 1.59-10.25; p=0.003) were significant predictors of tumor recurrence. The Kaplan-Meier plot of recurrence-free survival showed that obesity (log-rank p<0.001), current or former smoking (log-rank p=0.001), and a high-grade tumor (log-rank p=0.006) were associated with a shorter time interval until the first tumor recurrence.

Conclusion

The study found a high recurrence rate of NMIBC in Iran from January 2017 to January 2020, with the obesity, smoking history, and the high-grade tumor as contributing factors.

Intermediate and high-risk non-muscle-invasive bladder cancer: an overview of epidemiology, burden, and unmet needs

Bladder cancer ranks among the most common cancers globally. At diagnosis, 75% of patients have non-muscle-invasive bladder cancer (NMIBC). Patients with low-risk NMIBC have a good prognosis, but recurrence and progression rates remain high in intermediate- and high-risk NMIBC, despite the decades-long availability of effective treatments for NMIBC such as intravesical Bacillus Calmette-Guérin (BCG). The present review provides an overview of NMIBC, including its burden and treatment options, and then reviews aspects that counteract the successful treatment of NMIBC, referred to as unmet treatment needs. The scale and reasons for each unmet need are described based on a comprehensive review of the literature, including insufficient adherence to treatment guidelines by physicians because of insufficient knowledge, training, or access to certain therapy options. Low rates of lifestyle changes and treatment completion by patients, due to BCG shortages or toxicities and adverse events as well as their impact on social activities, represent additional areas of potential improvement. Highly heterogeneous evidence for the effectiveness and safety of some treatments limits the comparability of results across studies. As a result, efforts are underway to standardize treatment schedules for BCG, but intravesical chemotherapy schedules remain unstandardized. In addition, risk-scoring models often perform unsatisfactorily due to significant differences between derivation and real-world cohorts. Reporting in clinical trials suffers from a lack of consistent outcomes reporting in bladder cancer clinical trials, paired with an under-representation of racial and ethnic minorities in many trials.

An Association Study of Germline Variants in Bladder Cancer-Related Genes with the Prognosis of Non-Muscle Invasive Bladder Cancer

BACKGROUND

Various germline genetic variants are associated with the prognosis of non-muscle invasive bladder cancer (NMIBC). Germline variants in genes frequently somatically mutated in bladder cancer have not been studied thoroughly in relation to risk of recurrence or progression in NMIBC.

OBJECTIVE

To identify germline DNA variants in bladder carcinogenesis-related genes associated with recurrence or progression in NMIBC.

METHODS

We analysed associations between single-nucleotide polymorphisms (SNPs) and NMIBC recurrence and progression using data from the Nijmegen Bladder Cancer Study (NBCS, 1,443 patients). We included 5,053 SNPs within 46 genes known to have mutation, overexpression or amplification in bladder cancer. We included all recurrences in the statistical analysis and performed both single variant analysis and gene-based analysis. SNPs and genes that showed significant or suggestive association (false discovery rate P value < 20%) were followed-up in independent cohorts for replication analysis, through eQTL analysis and tests for association of tumour expression levels with NMIBC recurrence and progression.

RESULTS

Single variant analysis showed no statistically significant associations with recurrence or progression. In gene-based analysis, the aggregate effect of the 25 SNPs in the Cyclin D1 gene (CCND1) was statistically significantly associated with NMIBC recurrence (Punadj = 0.001, PFDR = 0.046), but not with progression (Punadj = 0.17, PFDR = 0.54). Validation analysis in independent cohorts did not confirm the association of CCND1 with NMIBC recurrence.

CONCLUSIONS

We could not identify reproducible associations between common germline variants in bladder carcinogenesis-related genes and NMIBC recurrence or progression.

Global trends in the epidemiology of bladder cancer: challenges for public health and clinical practice

Bladder cancer is among the ten most common cancers globally, causes considerable morbidity and mortality and is, therefore, a substantial burden for health-care systems. The incidence of bladder cancer is affected by demographic trends, most notably population growth and ageing, as well as exposure to risk factors, especially tobacco smoking. Consequently, the incidence has not been stable throughout the world over time, nor will it be in the near future. Further primary prevention efforts are of the utmost importance to reduce the medical and financial burden of bladder cancer on populations and health-care systems. Simultaneously, less-invasive and lower-cost approaches for the diagnosis of both primary and recurrent bladder cancers are required to address challenges posed by the increasing shortage of health-care professionals and limited financial resources worldwide. In this regard, urinary biomarkers have demonstrated promising diagnostic accuracy and efficiency. Awareness of the risk factors and symptoms of bladder cancer should also be increased in society, particularly among health-care professionals and high-risk groups. Studies investigating the associations between lifestyle factors and bladder cancer outcomes are scarce and should be a research priority. In this Review, we outline global trends in bladder cancer incidence and mortality, and discuss the main risk factors influencing bladder cancer occurrence and outcomes. We then discuss the implications, challenges and opportunities of these epidemiological trends for public health and clinical practice.

Adherence to lifestyle recommendations after non-muscle invasive bladder cancer diagnosis and risk of recurrence

BACKGROUND

Patients with non-muscle invasive bladder cancer (NMIBC) are at a high risk of tumor recurrence. It has not been previously investigated if adherence to cancer prevention recommendations lowers the risk of recurrence.

OBJECTIVES

We examined whether the standardized lifestyle score measuring adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations was associated with the risk of recurrence and progression among patients with NMIBC.

METHODS

The study population included patients diagnosed with primary NMIBC between 2014 and 2017 from the prospective cohort UroLife. Lifestyle was assessed at baseline (n = 979; reflecting the prediagnosis period) and 3-mo postdiagnosis (n = 885). The standardized 2018 WCRF/AICR score was constructed based on recommendations for body weight, physical activity, diet, and alcohol intake. We computed multivariable-adjusted HRs and 95% CIs using Cox proportional hazard regression models.

RESULTS

During a median follow-up time of 3.7 y, 320 patients developed ≥1 recurrence(s) and 49 experienced progression. Patients in the highest compared with the lowest tertile of postdiagnosis WCRF/AICR scores had a lower risk of first bladder cancer recurrence (HR: 0.74; 95% CI: 0.56, 0.98). No associations were observed for multiple recurrences (HR: 0.90; 95% CI: 0.70, 1.15) or for the baseline score with either first (HR: 1.07; 95% CI: 0.82, 1.40) or multiple recurrences (HR: 1.04; 95% CI: 0.82, 1.31). Improving lifestyle after diagnosis (per 1-point increase) was not significantly associated with the risk of first or multiple recurrence(s) (HR: 0.87; 95% CI: 0.74, 1.02; HR: 0.93; 95% CI: 0.80, 1.08, respectively). No associations were observed for bladder cancer progression, but the power was limited.

CONCLUSIONS

Better adherence to the WCRF/AICR cancer prevention recommendations 3 mo after NMIBC diagnosis, but not before diagnosis, is associated with a decreased risk of first bladder cancer recurrence. More studies evaluating postdiagnosis lifestyles are needed to provide solid support for lifestyle recommendations for cancer survivors.

American Cancer Society nutrition and physical activity guideline for cancer survivors

The overall 5-year relative survival rate for all cancers combined is now 68%, and there are over 16.9 million survivors in the United States. Evidence from laboratory and observational studies suggests that factors such as diet, physical activity, and obesity may affect risk for recurrence and overall survival after a cancer diagnosis. The purpose of this American Cancer Society guideline is to provide evidence-based, cancer-specific recommendations for anthropometric parameters, physical activity, diet, and alcohol intake for reducing recurrence and cancer-specific and overall mortality. The audiences for this guideline are health care providers caring for cancer survivors as well as cancer survivors and their families. The guideline is intended to serve as a resource for informing American Cancer Society programs, health policy, and the media. Sources of evidence that form the basis of this guideline are systematic literature reviews, meta-analyses, pooled analyses of cohort studies, and large randomized clinical trials published since 2012. Recommendations for nutrition and physical activity during cancer treatment, informed by current practice, large cancer care organizations, and reviews of other expert bodies, are also presented. To provide additional context for the guidelines, the authors also include information on the relationship between health-related behaviors and comorbidities, long-term sequelae and patient-reported outcomes, and health disparities, with attention to enabling survivors' ability to adhere to recommendations. Approaches to meet survivors' needs are addressed as well as clinical care coordination and resources for nutrition and physical activity counseling after a cancer diagnosis.

Limited Changes in Lifestyle Behaviours after Non-Muscle Invasive Bladder Cancer Diagnosis

The aim of our study was to investigate adherence to lifestyle recommendations and lifestyle changes after diagnosis in patients with non-muscle invasive bladder cancer (NMIBC). Second, we aimed to identify distinct trajectories of lifestyle change and their correlates. We analysed data of 935 patients with NMIBC from a prospective cohort study at six weeks (evaluating pre-diagnostic lifestyle), three months, and fifteen months after diagnosis. An overall lifestyle score (range 0-7) was calculated based on the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) recommendations focusing on diet, body mass index, and physical activity. Linear mixed models were used to analyse absolute lifestyle changes over time. Distinct trajectories of change were identified with latent class trajectory models. We found an overall lifestyle score of 3.3 which remained constant over time. The largest lifestyle changes were observed for the consumption of red and processed meat (-96 g/week) and fruit and vegetables (-38 g/day). Two to four trajectory groups were identified for each single lifestyle behaviour. Correlates differed per trajectory group. In conclusion, adherence to the WCRF/AICR recommendations was low. Small to moderate changes in and different trajectories of single lifestyle behaviours were observed. Effective strategies for lifestyle improvement are warranted.

Bladder cancer and exeRcise trAining during intraVesical thErapy-the BRAVE trial: a study protocol for a prospective, single-centre, phase II randomised controlled trial

INTRODUCTION

Non-muscle invasive bladder cancer (NMIBC) accounts for about 75% of newly diagnosed bladder cancers. The treatment for NMIBC involves surgical removal of the tumour followed by 6 weekly instillations of immunotherapy or chemotherapy directly into the bladder (ie, intravesical therapy). NMIBC has a high rate of recurrence (31%-78%) and progression (15%). Moreover, bladder cancer and its treatment may affect patient functioning and quality of life. Exercise is a safe and effective intervention for many patient with cancer groups, however, no studies have examined exercise during intravesical therapy for NMIBC. The primary objective of the Bladder cancer and exeRcise trAining during intraVesical thErapy (BRAVE) trial is to examine the safety and feasibility of an exercise intervention in patients with bladder cancer undergoing intravesical therapy. The secondary objectives are to investigate the preliminary efficacy of exercise on health-related fitness and patient-reported outcomes; examine the social cognitive predictors of exercise adherence; and explore the potential effects of exercise on tumour recurrence and progression.

METHODS AND ANALYSIS

BRAVE is a phase II randomised controlled trial that aims to include 66 patients with NMIBC scheduled to receive intravesical therapy. Participants will be randomly assigned to the exercise intervention or usual care. The intervention consists of three supervised, high-intensity interval training sessions per week for 12 weeks. Feasibility will be evaluated by eligibility, recruitment, adherence and attrition rates. Preliminary efficacy will focus on changes in cardiorespiratory fitness and patient-reported outcomes from baseline (prior to intravesical therapy) to pre-cystoscopy (3 months). Cancer outcomes will be tracked at 3 months, and 1-year follow-up by cystoscopy. Analysis of covariance will compare between-group differences at post-intervention (pre-cystoscopy) for all health-related fitness and patient-reported outcomes.

ETHICS AND DISSEMINATION

The study was approved by the Health Research Ethics Board of Alberta-Cancer Committee (#20-0184). Dissemination will include publication and presentations at scientific conferences and public channels.

TRIAL REGISTRATION NUMBER

NCT04593862; Pre-results.

Association between blood pressure and BMI with bladder cancer risk and mortality in 340,000 men in three Swedish cohorts

BACKGROUND

The relation between obesity, blood pressure (BP) and bladder cancer (BC) risk and mortality remains unclear, partially due to potential confounding by smoking, the strongest risk factor for BC, and not accounting for tumor stage and grade in such studies. We investigated body mass index (BMI) and BP in relation to BC risk by stage and grade, and BC-specific mortality, including separately among never-smokers aimed at minimizing confounding by smoking.

METHODS

We analyzed 338,910 men from three Swedish cohorts, with 4895 incident BC's (940 among never-smokers) during follow-up. Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals adjusted for smoking status. HRs for BMI and BP were corrected for their regression dilution ratios, calculated from 280,456 individuals with 758,641 observations.

RESULTS

Body mass index was positively associated with non-muscle invasive BC (NMIBC, HR per 5 kg/m2 , 1.10 [1.02-1.19]) and NMIBC grade 3 (HR 1.17 [1.01-1.34]) in the full cohort, with similar effect sizes, albeit non-significant, among never-smokers. Systolic BP was positively associated with muscle-invasive BC (MIBC, HR per 10 mmHg, 1.25 [1.00-1.55]) and BC-specific mortality (HR 1.10 [1.01-1.20]) among never-smokers, with weaker and non-significant associations in the full cohort.

CONCLUSIONS

In an analyses of BMI, BP and BC risk by stage and grade among men, we found modest positive associations between BMI and NMIBC and NMIBC grade 3. SBP was positively associated with MIBC and BC-specific mortality in an analysis of never-smokers, which may reflect the association, un-confounded by smoking, also in a broader population.