Latest Findings on Bladder Cancer Risk Factors

Bladder cancer affects the body’s ability to urinate and can inflict pain. Healthcare professionals understand what causes this disease, though researchers are finding new causes. What are the latest findings on bladder cancer risk factors? Recent studies have discussed emerging causes and the continued importance of established reasons.

The Latest Developments in Bladder Cancer Risk Factors

Discovering new causes of cancer helps medical professionals diagnose and treat these diseases. What new risk factors have emerged for bladder cancer? Here are four causes to watch in the future. 

1. Genetic Predisposition

The precise causes of bladder cancer have yet to be discovered in the scientific community. However, researchers have recently discovered that genetic predisposition could lead to this disease. You could inherit gene changes from your parents, such as GSTM1 or NAT2. With these mutations, it is more challenging to break down toxins.¹

Gene syndromes could also significantly affect your predisposition to bladder cancer throughout your life. For instance, the retinoblastoma (RB1) gene could mutate and heighten your risk of bladder cancer. While you may associate Lynch syndrome with the colon, experts say it can increase the risk of cancer in your bladder and the urinary tract.¹

When you have a genetic predisposition to bladder cancer, an unhealthy lifestyle could be one of the most crucial risk factors. A 2022 BJUI International study investigated the association between polygenic risk scores and bladder cancer risks. The researchers concluded genetic predisposition with unhealthy behaviors combine to increase your risk of this disease.²

2. Imbalanced Microbiome

Your microbiome includes the microorganisms living inside your body. While some think bacteria and fungi work against your well-being, these factors are essential to remaining healthy. Dysbiosis occurs when there is an imbalance in your microbiome, and it could lead to bladder cancer. The development is critical for understanding this type of cancer.

Recently, researchers suggested that microbiome dysbiosis and immune dysregulations could be bladder cancer risk factors. A 2024 Cancers study examined this medical occurrence to understand its potential as a diagnostic measure. Cytokine activity and immune pathway enrichment led researchers to conclude there was an immune modulatory relation. Therefore, it could have implications for bladder cancer.³

“Our findings indicate that the urinary microbiome may reflect both microbial and immune dysregulations of the tumor microenvironment in bladder cancer,” the study said. “Given the potential biomarker species identified, the urinary microbiome may provide a non-invasive, more sensitive, and more specific diagnostic tool, allowing for the earlier diagnosis of patients with bladder cancer.”

3. Diesel Exhaust Emission Exposure

Workplace exposure is a known bladder cancer risk factor regardless of the industry in which you work. Scientists understand that fumes can affect firefighters, hairdressers, and truck drivers.¹ However, recent research has focused on diesel and how associated machines can increase the risk of diseases. Workers and organizations must be careful around these emissions.

The International Agency for Research on Cancer (IARC) listed diesel engine exhaust and outdoor air pollution as agents with limited evidence in humans.⁴  A 2024 Environmental Health Perspectives study found a positive monotonic pattern in the hazard ratios for bladder cancer. However, the results were not as statistically significant as other factors.⁵  

Finding causation between diesel exhaust emissions and bladder cancer would be significant for medical research. With more research and conclusive evidence, scientists could link this risk factor to one of the most common forms of cancer. Bladder cancer constitutes about 4% of cancers in America, with about 83,000 new cases annually.⁶

4. Pelvic Radiotherapy

Pelvic radiotherapy (RT) may be necessary to treat cancer cells in your pelvis. Healthcare professionals enact this procedure to combat various cancers, such as cervical, rectal, and bladder. While typically effective, it could negatively affect your bladder with secondary tumors. Therefore, the treatment could come into question for some people.

A 2022 Frontiers in Oncology review examined the relationship between pelvic RT and secondary bladder cancer. For this study, the researchers investigated 318,000 observations of primary cancers in the pelvic cavity. The regression analysis found an increased risk of secondary bladder cancer after RT in the early latency.⁷

Established Bladder Cancer Risk Factors Remain

While new risk factors are emerging, researchers continue improving their knowledge of established causes of bladder cancer. Here are four known origins of this disease.

1. Age

While some risk factors are preventable, age is not one of them. Older people — especially men — are more prone to develop bladder cancer. The American Cancer Society (ACS) says the risk increases with age, and 90% of people with the disease are over 55 years old.¹

Age is among the most common factors because it combines what your body has been through. In previous years, you may have been exposed to smoke, chemicals at work, or pollutants in your area. The body also becomes less strong over time due to a less effective immune system and cells less able to fight disease.

Bladder cancer survival depends on your age, according to a 2023 study. The review published in Cancer Control identified over 117,000 people with bladder cancer and divided them into four age groups. Researchers found the oldest group — those 75 years or older — had the shortest survival compared to those under 54. Therefore, the age of diagnosis is a significant predictor for bladder cancer survival.⁸

2. Smoking Tobacco

Another established risk factor for bladder cancer is smoking, especially tobacco products. When you smoke cigarettes or related products, you inhale carcinogenic chemicals and send them into your bloodstream. The kidneys filter this smoke but can only do so much before it affects your urine and bladder lining.

How impactful is smoking? The ACS says smoking makes you at least three times as likely to get bladder cancer. In fact, smoking causes around half of all bladder-related diseases.¹ This activity can damage your cells and develop abnormalities. If you quit, your cancer risk will likely decline.

Bladder cancer is more likely if you smoke tobacco. However, other forms of smoking have less association with this disease. A 2022 Jama Network study followed 1,472 adults with non-muscle-invasive bladder cancer (NMIBC), with around two-thirds being current or former smokers. The researchers found no association between recurrence and pipe, cigar, e-cigarette, and marijuana smokers.⁹ 

3. Arsenic Levels in Water

Municipal store-bought water typically contains minerals such as fluoride and magnesium. However, excess arsenic in your water could adversely affect your body and cause bladder cancer. You could see municipal water with high arsenic levels in some sections of the U.S. and various South American and Asian countries.¹⁰

High concentrations of arsenic can cause bladder cancer because they damage your DNA. The metalloid can create oxygen-based radicals through oxidative stress, thus causing an imbalance between free radicals and antioxidants. Arsenic’s oxidative stress can lead to more problems like infertility in male and female reproductive systems.¹¹

While arsenic can be carcinogenic, experts say it could be an anticancer agent. A 2023 American Journal of Translational Research study analyzed its effects on gene expression, especially ACTB, BACH1, NME2, RBBP4, PARP1, PML, and downstream genes. The researchers found arsenic can alter expression and exert anticancer functions.¹²

4. Medications

You may have medical conditions requiring you to take medications. Depending on the active ingredients and dosage, they could increase your risk of bladder cancer. For instance, pioglitazone is a medication people use to treat high blood sugar levels and type 2 diabetes. That said, the ACS says high doses may increase your risk of bladder cancer.¹ 

While oxidative stress plays a role in pioglitazone’s adverse effects, so do peroxisome proliferator-activated receptor gamma (PPAR-g) proteins. Research suggests PPAR-g mutations and genomic alternations in bladder cancer are common¹³. Additionally, loss of signaling could cause tumors to form in the bladder.

Why Finding New Bladder Cancer Risk Factors Is Essential

Bladder cancer’s prevalence worldwide — especially in men — means more research and studies are necessary to save lives. While this disease has a relatively high survival rate, it could be fatal without proper treatment. Early detection is crucial to ensure you combat the cancer early.

The five-year relative survival rate for bladder cancer depends on how invasive it is. Experts say it is about 96%¹⁴ for people with surface-layer bladder cancer, and 69% if it has not spread beyond the bladder. If the disease is at a later stage, it becomes more complex to treat.

While research on bladder cancer treatment continues, scientists have found productive developments. For instance, new targeted therapies have led to novel treatments and drugs. Medical studies are comparing erdafitinib and chemotherapy to see its effect on people with advanced bladder cancer and gene-altered tumors.¹⁵ Gene therapies, antibody-drug conjugates, and other alternatives are additional options for the future of bladder cancer research.

Understanding Bladder Cancer Risk Factors and Future Treatments

While bladder cancer primarily affects men, it is essential to understand the risk factors for anybody who develops this disease. Scientists have established these causes, and more are emerging following studies and clinical trials. This new information allows healthcare professionals to improve targeted treatment and help those affected.

Learning about these risk factors helps you understand what you can and cannot control regarding the disease. For instance, your genetic predisposition may cause mutations and make it harder to break down toxins. Conversely, you have more control over causes like diesel exhaust emissions and pelvic RT.

With new risk factors emerging, experts are also finding developments on the known ones. For instance, researchers found tobacco can lead to bladder cancer, whereas other smoking substances did not associate with recurrence.⁹ Further research will give scientists more direction for improving bladder cancer treatments.

Sources:

1. American Cancer Society. Bladder Cancer Risk Factors.
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15. National Cancer Institute. Advances in Bladder Cancer Research.