Sex difference in presentation and outcomes of bladder cancer: biological reality or statistical fluke?

Global burden of bladder cancer mortality in 2020 and 2040 according to GLOBOCAN estimates

INTRODUCTION

In 2020, bladder cancer (BC) was the seventh most prevalent cancer in the world, with 5-year prevalence of more than 1.7 million cases. Due to the main risk factors-smoking and chemical exposures-associated with BC, it is considered a largely preventable and avoidable cancer. An overview of BC mortality can allow an insight not only into the prevalence of global risk factors, but also into the varying efficiency of healthcare systems worldwide. For this purpose, this study analyzes the national mortality estimates for 2020 and projected future trends up to 2040.

MATERIALS AND METHODS

Age-standardized mortality rates per 100,000 person-years of BC for 185 countries by sex were obtained from the GLOBOCAN 2020 database, operated by the International Agency for Research on Cancer (IARC). Mortality rates were stratified according to sex and Human Development Index (HDI). BC deaths were projected up to 2040 on the basis of demographic changes, alongside different scenarios of annually increasing, stable or decreasing mortality rates from the baseline year of 2020.

RESULTS

In 2020, nearly three times more men died from BC than women, with more than 210,000 deaths in both sexes combined, worldwide. Regardless of gender, more than half of the total BC deaths were from countries with a very high HDI. According to our projections, while the number of deaths for men can only increase up to 54% (from 159 to around 163-245 thousand), for women it is projected to increase two- to three-fold (from 50 to around 119-176 thousand) by 2040. The burden of BC mortality in countries with a very high HDI versus high HDI appears to converge by 2040 for both sexes.

CONCLUSION

Opposite mortality trends by gender highlight the urgent need for immediate interventions to expand anti-tobacco strategies, especially for women. The implementation of more strict occupational health and safety regulations could also prevent exposures associated with BC. Improving the ability to detect BC earlier and access to treatment can have a significant positive impact on reducing mortality rates, minimizing economic costs, and enhancing the quality of life for patients.

Gender and cystectomy for bladder cancer: A high-volume tertiary urologic care center experience

BACKGROUND

Differences have often been reported in the outcomes of bladder cancer (BC) patients according to gender.

OBJECTIVE

This study aims to provide data on patients undergoing radical cystectomy (RC) in a high-volume tertiary urologic center and to assess whether gender discrepancies do exist in terms of surgical options and clinical outcomes.

MATERIALS AND METHODS

Consecutive BC patients treated between 2016 and 2020 at a single center (Careggi University Hospital, Florence, Italy) were included in the study. The impact of gender on disease stage at diagnosis, overall survival (OS), and type of surgery was analyzed.

RESULTS

The study series comprised 447 patients (85 females and 362 males). At a median follow-up of 28.3 months (IQR: 33.5), OS was 52.6% and cancer-specific survival was 67.6%. Significant differences in OS emerged for age, acute myocardial infarction (AMI), Charlson Comorbidity Index (CCI), pT, and pN. OS rates were higher in patients undergoing robot-assisted surgery and in those receiving open orthotopic neobladder (ONB) (p = 0.0001). No statistically significant differences were found between male and female patients regarding surgical offer in any age group, surgical time, early postoperative complications, pathologic stage, and OS.

CONCLUSIONS

After adjustment for pathologic tumor stage and treatment modalities, female and male patients showed similar oncologic outcomes. Further studies should be undertaken to evaluate functional results in women subjected to RC.

The trend of schistosomiasis related bladder cancer in the lake zone, Tanzania: a retrospective review over 10 years period

INTRODUCTION

Bladder cancer is a possible outcome of chronic urinary schistosomiasis in many endemic countries. In Tanzania, the Lake Victoria area is one of the areas with the highest prevalence of urinary schistosomiasis and higher incidences of squamous cell carcinoma (SCC) of the urinary bladder. A previous study in the area over one decade (2001-2010) showed SCC to be common in patients aged below 50 years. With various prevention and intervention programs there are likely to be notable changes in schistosomiasis-related urinary bladder cancer, which is currently unknown. Updated information on the status of SCC in this area will be useful for giving an insights into efficacy of control interventions implemented and help guide the initiation of new ones. Therefore, this study was done to determine the current trend of schistosomiasis-related bladder cancer in lake zone, Tanzania.

METHODS

This was a descriptive retrospective study of histologically confirmed urinary bladder cancer cases diagnosed at the Pathology Department of Bugando Medical Centre over 10 years period. The patient files and histopathology reports were retrieved and information was extracted. Data were analyzed using Chi-square and student t-test.

RESULTS

A total of 481 patients were diagnosed with urinary bladder cancer during the study period whereby, 52.6% were males and 47.4% were females. The mean age regardless of histological type of cancer was 55 ± 14.2 years. The SCC was the commonest histological type accounting for 57.0%, followed by transitional cell carcinoma 37.6%, and 5.4% were adenocarcinomas. The Schistosoma haematobium eggs were observed in 25.2% and were commonly associated with SCC (p = 0.001). Poorly differentiated cancers were observed mostly in females (58.6%) compared to males (41.4%) (p = 0.003). Muscular invasion of the urinary bladder by cancer was observed in 11.4% of the patients, and this was significantly higher in non-squamous than in squamous cancers (p = 0.034).

CONCLUSION

Schistosomiasis-related cancers of the urinary bladder in the Lake zone of Tanzania is still a problem. Schistosoma haematobium eggs were associated with SCC type indicating the persistence of infection in the area. This calls for more efforts on preventive and intervention programs to reduce the burden of urinary bladder cancer in the lake zone.

Gender and Advanced Urothelial Cancer: Outcome, Efficacy and Toxicity following Chemotherapy

Background and Objectives: The incidence of urothelial cancer in males is higher than in females; however, females have a higher risk of recurrence and progression. The aim of our study was to report the effect of gender on the oncological outcome in advanced urothelial cancer. Materials and Methods: In our retrospective study, all patients had undergone primary surgical treatment for urothelial cancer and were affected by stage IV disease at the time of chemotherapy. Response to therapy and toxicity were evaluated. Subgroups were analyzed for tumour presentation, first- and second-line treatment response, progression-free survival (PFS) and overall survival (OS). Results. Seventy-five patients, 18 (24%) females and 57 (76%) males, were considered. Investigation into the distribution of individual characteristics according to gender revealed a significant difference only for smoking, with a prevalence of smokers in women (p = 0.029). At the end of follow-up, OS was higher in females (27.5% vs. 17.4%; p = 0.047). Smoking did not significantly influence OS (p = 0.055), while univariate Cox regression analysis confirmed that males had a higher risk of death (HR = 2.28, 95% CI 0.99–129 5.25), with borderline statistical significance (p = 0.053). Men showed higher PFS than women both after first-line (p = 0.051) and second-line chemotherapy (p = 0.018), with a lower risk of progression (HR = 0.29, 95% CI 0.10–0.86; p = 0.026). No differences were found between genders with regard to toxicity. Conclusions. In our series, PFS rates following first- and second-line therapies for advanced urothelial carcinoma confirmed that females have a greater risk of progression than males.

Dysuria therapeutic agents as an independent prognostic factor for the primary recurrence of non-muscle invasive bladder cancer: a propensity score matching study

OBJECTIVE

To investigate if the use of therapeutic agents for dysuria is a risk factor for the primary recurrence of non-muscle invasive bladder cancer (NMIBC).

METHODS

First, patients with NMIBC were divided into two groups: the non-recurrence group and the recurrence group. Patient characteristics were compared between both groups. The risk factors of recurrence that were statistically different between the two groups were identified by multivariate analysis. Second, we divided the patients into risk and non-risk groups, and differences in the recurrence-free survival (RFS) between the two groups were analyzed before and after propensity score matching (PSM).

RESULTS

A total of 162 patients were included, with 84 patients in the non-recurrence group and 78 patients in the recurrence group. In the multivariate analysis, the intake of dysuria agents and bacillus Calmette-Guérin (BCG) therapy were independent factors. The RFS results in terms of the intake of dysuria agents were statistically significant before and after PSM analysis, but no factors were significantly different between the BCG and non-BCG groups after PSM.

CONCLUSIONS

Therapeutic agents for dysuria might be at an independent risk factor for NMIBC recurrence. This trial is registered with the UMIN Clinical Trials Registry under the number UMIN000036097 (https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno = R000041122).

Cancer-specific survival by stage of bladder cancer and factors collected by Mallorca Cancer Registry associated to survival

Background

Information about survival by stage in bladder cancer is scarce, as well as about survival of non-invasive bladder cancer. The aims of this study are: 1) to find out the distribution of bladder cancer by stage; 2) to determine cancer-specific survival by stage of bladder cancer; 3) to identify factors that explain and predict the likelihood of survival and the risk of dying from these cancers.

Methods

Incident bladder cancer cases diagnosed between 2006 and 2011 were identified through the Mallorca Cancer Registry. Inclusion criteria: cases with code C67 according to the ICD-O 3rd edition with any behaviour and any histology, except lymphomas and small cell carcinomas. Cases identified exclusively through the death certificate were excluded. We collected the following data: sex; age; date and method of diagnosis; histology according to the ICD-O 3rd edition; T, N, M and stage at the time of diagnosis; and date of follow-up or death. End point of follow-up was 31 December 2015. Multiple imputation (MI) was performed to estimate cases with unknown stage. Cases with benign or indeterminate behaviour were excluded for the survival analysis. Actuarial and Kaplan-Meier methods and Cox regression models were used for survival analysis.

Results

One thousand nine hundred fourteen cases were identified. 14% were women and 65.4% were 65 years or older. 3.9% had no stage (benign or undetermined behaviour) and 11.5% had unknown stage. After MI, 37.5% were in stage Ta (non-invasive papillary carcinoma), 3.2% in stage Tis (carcinoma in situ), 34.3% in stage I, 11.7% in Stage II, 4.3% in stage III, and 9.0% in stage IV. Survival was 76% at 5 years. Survival by stage: 98% at stage Ta, 90% at stage Tis, 85% at stage I, 45% at stage II, 35% at stage III, and 7% at stage IV. The Cox model showed that age, histology, and stage, but not sex, were associated with survival.

Conclusion

Bladder cancer survival vary greatly with stage, among both non-invasive and invasive cases. The percentage of non-invasive cancers is high. Stage, age, and histology are associated to survival.

The radiotherapy cancer patient: female inclusive, but male dominated

Background: The sex-neutral language used in preclinical and clinical research intends to be inclusive of both the female and the male population, but the practice of data pooling prevents the detection of the impact of sex on cancer biology and response to medications and treatment. This study aimed to examine the consideration of sex as biological variable in the evaluation of radiation therapy in preclinical and clinical studies.Methods: Preclinical and clinical studies published over a 12-month period were reviewed for the reporting of cells, animal or patient sex and the inclusion of sex as a biological variable in both study design and data analysis.Results: A total of 321 articles met the inclusion criteria: 41 (13%) preclinical and 280 (87%) clinical studies. Two articles reported separate outcome data for males and females. Where the sex of participants was stated (230/280 (82%), 81% reported a larger number of male participants, compared to females. Less than half (45%) of studies used sex as a variable in data analysis. Sex disparity was not dependent on study location but may be more prominent in certain cancer sites. In preclinical studies, sex was at best stated in those reporting on animals (48% of studies).Conclusion: Referring to a radiotherapy cancer patient, the literature is female inclusive, but a gap does exist when it comes to consideration of sex in data analysis. The pooled analysis of female and male data could introduce statistical biases and prevent the identification of key sex-specific biological subtilities that do affect radiation responses.

The impact of gender on oncologic outcomes of bladder cancer

PURPOSE OF REVIEW

The purpose of this article is to review the current literature on the impact of gender on oncologic outcomes of bladder cancer (BCa).

RECENT FINDINGS

Women are more likely to experience disease recurrence, progression, and/or death across all disease states. Furthermore, women are less likely to respond to intravesical therapy for nonmuscle invasive BCa. These disparities are explained by several hypotheses such as differential exposure to environmental carcinogens, hormonal factors, and/or disease management. Additionally, it has been shown that women suffer from delays in diagnosis because of inefficiencies in healthcare delivery. On genomic analyses, women were found to be more likely to harbor basal subtypes of BCa compared with men.

SUMMARY

A steadily growing body of evidence reveals that women present with more advanced BCa and have stage-for-stage worse outcome compared with men. The underlying mechanisms for this gender difference are multifactorial. Further studies are needed to elucidate the molecular underpinning of this gender-gap and subsequently explore potential novel gender-specific management strategies.

Sex Differences in Urothelial Bladder Cancer Survival

BACKGROUND

While urinary bladder cancer is consistently more common in men worldwide, women have poorer prognosis. The aim of this study was to outline sex differences in prognostic factors and clinical management and to explore whether these can explain the poorer urinary bladder cancer outcome in women.

PATIENTS AND METHODS

We performed a population-based cohort study including all patients diagnosed with urothelial bladder cancer between 1997 and 2014 at age 18 to 89 who had data recorded in the Swedish Urinary Bladder Cancer Register (n = 36,344). Female-to-male odds ratios for clinical management parameters were estimated by logistic regression. To quantify sex differences in bladder cancer-specific survival, we estimated empirical survival proportions and mortality rates as well as applied flexible parametric models to estimate female-to-male hazard ratios and survival proportions over follow-up. Adjusted models included age, year, World Health Organization grade, stage, marital status, education, health care region, birth country, and comorbidity.

RESULTS

Except for an adverse stage distribution in women, we found no evidence of unequal clinical management. Among those diagnosed with bladder cancer, women had a higher bladder cancer mortality (adjusted hazard ratio, 1.15; 95% confidence interval, 1.08-1.23) driven by muscle-invasive tumors (adjusted hazard ratio, 1.24; 95% confidence interval, 1.14-1.34). The female survival disadvantage was confined to the first 2 years after diagnosis.

CONCLUSION

The excess bladder cancer mortality in women is limited to those diagnosed with muscle-invasive tumors and cannot be explained by the examined clinicopathologic factors. Further investigations of sex differences in therapeutic procedures and outcomes, including complications, of muscle-invasive bladder cancer, must be performed.

Gender-related Outcome in Bladder Cancer Patients undergoing Radical Cystectomy

Background: The impact of gender on oncological outcome after radical cystectomy (RC) is not fully understood yet. The aim of the study was to evaluate gender-related differences in histopathological parameters and prognosis of patients with bladder cancer undergoing RC.

Methods: A retrospective analysis of a 10-year single-center cystectomy database was performed. Kaplan-Meier survival and Cox-regression analyses with sex-specific interactions were performed to determine the impact of gender on recurrence-free survival (RFS), cancer-specific survival (CSS), and overall survival (OS), in addition to established clinicopathological factors.

Results: 259 patients (212 [81.8%] men and 47 [18.2%] women) were enrolled. Although women had a greater propensity for extravesical (≥pT3) disease (53.2% vs. 33.9%, p=0.03) and heterotopic urinary diversion (72.3% vs. 49.5%, p=0.006), gender did not independently predict RFS, CSS or OS on multivariate analysis. Extravesical tumor disease was the sole independent predictor concerning RFS (hazard ratio [HR]=4.70; p<0.001), CCS (HR=2.77; p=0.013), and OS (HR=1.93; p=0.041). Orthotopic urinary diversion (HR=0.36; p=0.002) had an independent effect only on RFS. Rates of 5-year RFS (73.7% vs. 48.3%; p=0.001), CSS (72.5% vs. 44.9%; p<0.001) and OS (62.6% vs. 37.8%; p<0.001) were higher in orthotopic versus heterotopic diversions.

Conclusion: In our series, women presented with more advanced tumors and higher rates of heterotopic urinary diversions, but their survival outcome was not significantly inferior to that of men. Extravesical disease was independently related to poorer survival after RC.

Incidence and Survival of urothelial carcinoma of the urinary bladder in Norway 1981-2014

Background

Urothelial carcinoma of the urinary bladder (UCB) is the 4^th most common cancer type in men in developed countries, and tumor recurrence or progression occurs in more than half of the patients. Previous studies report contradictory trends in incidence and survival over the past decades. This article describes the trends of UCB incidence and survival from 1981 to 2014, including both invasive and non-invasive UCB using data from the Cancer Registry of Norway.

Methods

In Norway, 33,761 patients were diagnosed with UCB between 1981 and 2014. Incidence and 5-year relative survival were calculated, stratified by sex, morphology, stage, age and diagnostic period. Age-period-cohort models were used to distinguish period- and cohort effects. Temporal trends were summarized by calculating the average absolute annual change in incidence and relative survival allowing for breaks in this trend by incorporating a joinpoint analysis. Excess mortality rate ratios (EMRR) quantify the relative risks by using a proportional excess hazard model.

Results

The incidence of UCB in men increased from 18.5 (1981-85) to 21.1 (1991-95) per 100 000 person-years and was rather stable thereafter (1996–2014). The incidence rates of UCB were lower in women increasing linearly from 4.7 to 6.2 over the past 34 years (p = 5.9 · 10^-7). These trends could be explained by an increase of the incidence rates of non-invasive tumors. Furthermore, the observed pattern seemed to represent a birth cohort effect. Five-year relative survival increased annually with 0.004 in men (p = 1.3 · 10^-6) and 0.003 in women (p = 4.5 · 10^-6). There is a significant increase over the past 34 years in survival of UCB in both genders for local tumors but not for advanced stages.

Conclusions

Increasing and stable incidence trends mirror little improvement in primary and secondary prevention of UCB for more than three decades. Survival proportions increased only marginally. Thus, any changes in treatment and follow-up care did not lead to notable improvement with respect to survival of the patients. High estimates of preventable cases together with large recurrence rates of this particular cancer type, demand more research on prevention guidelines, diagnostic tools and treatment for UCB.

Gender and Bladder Cancer: A Collaborative Review of Etiology, Biology, and Outcomes

CONTEXT

The incidence of bladder cancer is three to four times greater in men than in women. However, women are diagnosed with more advanced disease at presentation and have less favorable outcomes after treatment.

OBJECTIVE

To review the literature on potential biologic mechanisms underlying differential gender risk for bladder cancer, and evidence regarding gender disparities in bladder cancer presentation, management, and outcomes.

EVIDENCE ACQUISITION

A literature search of English-language publications that included an analysis of the association of gender with bladder cancer was performed using Pubmed. Ninety-seven articles were selected for analysis with the consensus of all authors.

EVIDENCE SYNTHESIS

It has been shown that the gender difference in bladder cancer incidence is independent of differences in exposure risk, including smoking status. Potential molecular mechanisms include disparate metabolism of carcinogens by hepatic enzymes between men and women, resulting in differential exposure of the urothelium to carcinogens. In addition, the activity of the sex steroid hormone pathway may play a role in bladder cancer development, with demonstration that both androgens and estrogens have biologic effects in bladder cancer in vitro and in vivo. Importantly, gender differences exist in the timeliness and completeness of hematuria evaluation, with women experiencing a significantly greater delay in urologic referral and undergoing guideline-concordant imaging less frequently. Correspondingly, women have more advanced tumors at the time of bladder cancer diagnosis. Interestingly, higher cancer-specific mortality has been noted among women even after adjusting for tumor stage and treatment modality.

CONCLUSIONS

Numerous potential biologic and epidemiologic factors probably underlie the gender differences observed for bladder cancer incidence, stage at diagnosis, and outcomes. Continued evaluation to define clinical applications for manipulation of the sex steroid pathway and to improve the standardization of hematuria evaluation in women may improve future patient outcomes and reduce these disparities.

PATIENT SUMMARY

We describe the scientific basis and clinical evidence to explain the greater incidence of bladder cancer in men and the adverse presentation and outcomes for this disease in women. We identify goals for improving patient survival and reducing gender disparities in bladder cancer.