Though bladder cancer may not be as widely discussed as other, more prominent types of cancer, it’s more common than many people realize. In fact, it’s the fourth most common type of cancer in men. Here, we’re exploring the causes, symptoms, prognosis, and more for this type of cancer, which disproportionately affects older populations.
Types of Bladder Cancer
Cancer of the bladder occurs when the cells that compose the urinary bladder grow out of control and become cancerous. This can lead to tumors developing and can further turn metastatic if the cancer spreads to other parts of the body. Several different kinds of bladder cancer can occur, though some are more prevalent than others.
Urothelial carcinoma.
Also known as transitional cell carcinoma, this type of bladder cancer is by far the most common one. With this type, the cancer develops within the urothelial cells that line the interior of the bladder, ureters, and urethra.
Squamous cell carcinoma.
Squamous cells are thin, flat cells that line the urethra and form in the bladder after prolonged irritation or inflammation. Squamous cell carcinoma is rare and almost always invasive.
Adenocarcinoma.
This is a very rare form of bladder cancer that forms in the bladder’s glandular cells. Adenocarcinomas are almost always invasive and make up under 2% of bladder cancer cases.
Bladder cancers are often described in relation to how far they have spread into the bladder wall. The cancer is labeled non-invasive if only the inner layer of cells inside the bladder has been affected, and it is called invasive if the cancerous cells have grown deeper into the layers of the bladder wall. The latter is more likely to become metastatic and is more difficult to treat.
Bladder cancers can also be classified into two different subtypes, depending on how the carcinomas grow. Papillary carcinomas grow in slender projections from the inner surface of the bladder toward the center, whereas flat carcinomas don’t grow toward the center at all and are typically either non-invasive or grow invasively into the deeper layers of the bladder.
Signs & Symptoms
Bladder cancer can sometimes be detected early due to urinary symptoms that often appear even in the cancer’s early stages. “The most common early sign of bladder cancer is hematuria, or blood in the urine,” says Dr. Derek Holland, a medical oncologist with Tennessee Oncology. “This is usually painless, but at times can be associated with burning, frequent urination, or difficulty urinating. The overlap of these symptoms with those of urinary tract infections can sometimes delay diagnosis.” Blood in the urine can also be caused by conditions such as kidney stones or benign tumors. Regardless, it’s important to be checked out by a doctor if you notice these symptoms.
According to Dr. Amar Singh, a urological oncologist with Erlanger Urology, “Different bladder cancers can present differently depending on the type, size, and location within the bladder. Bladder cancers that are near where the kidneys empty into the bladder can present as flank pain, whereas those that are near the bladder outlet can cause difficulty urinating.” Over time, bladder cancer can also spread to other parts of the body, causing existing symptoms to advance and new ones to develop, such as lower back pain, loss of appetite or weight loss, chronic fatigue, swelling in the feet, and bone pain.
Causes & Risk Factors
Like many other serious diseases and conditions, a definitive cause of bladder cancer cannot currently be pinpointed. However, experts agree that it’s typically the combined result of genetics and additional risk factors. The following may increase risk of bladder cancer:
Family or personal history of cancer.
Having an immediate family member with a history of bladder cancer may increase your risk of developing it; however, it’s rare for this type of cancer to run in families. If you personally have had bladder cancer in the past, you might be at higher risk of having it again.
Previous cancer treatment.
Unfortunately, some drugs used to treat other cancers may increase risk of bladder cancer, and if you’ve ever undergone radiation therapy aimed in the pelvic area, this can lead to an elevated risk of bladder cancer as well.
Increasing age, particularly for males.
Men are considerably more likely to develop bladder cancer than women are, and according to Dr. Holland, “The risk for bladder cancer increases with age. Most bladder cancers are diagnosed in patients over the age of 65.”
Smoking or exposure to certain chemicals.
Due to the urinary system’s role of filtering out waste and harmful substances out of the blood and into the bladder, exposure to toxic chemicals such as arsenic may lead to cancer developing in the bladder. “The most important risk factor for bladder cancer is smoking,” says Dr. Holland. “Other environmental toxins have also been associated with cancer of the bladder. Occupations with higher risks of bladder cancer include metal workers, miners, and those in the textile and rubber industries.”
Chronic bladder inflammation.
Chronic urinary infections or inflammation – which can be caused by things like long-term use of a catheter – can increase risk of squamous cell carcinoma specifically.
Diagnosis
There are several tests that one might undergo to determine a diagnosis of bladder cancer. A scope can be used to examine the inside of the bladder (called a cystoscopy) for any sign of disease. “Any suspicious lesions are removed in the operating room with an electric loop and sent to a pathologist to confirm that the lesion is indeed bladder cancer,” says Dr. Singh. Urine samples might also be collected, and imaging tests can be used to identify cancer not only in the bladder, but elsewhere in the body.
Treatment & Outlook
Once a diagnosis of bladder cancer has been confirmed, there are several paths of treatment that can be taken.
“The treatment depends on the depth of invasion into the bladder and the aggressiveness of the cancer type,” Dr. Singh says. “All treatment strategies should be led by a urologist who can explain the treatment options based on the type of bladder cancer the patient has. Once the options have been explained, the urologist can work with the patient to find the option that is best for that particular patient.”
Surgery to remove the cancerous cells is often the first choice for early stage treatment, and it’s not uncommon for doctors to prescribe a combination of different approaches to best combat the disease. “If the tumor has invaded the muscle layer of the bladder, then a removal of the entire bladder (cystectomy) is performed,” Dr. Holland explains. “This is often done in combination with chemotherapy, either before or after surgery. For those who cannot undergo cystectomy, radiation therapy is an option.” In the past, having a cystectomy meant that patients would need to have a bag attached to their abdomen to collect urine, but that is not necessarily the case anymore. “Newer treatment options allow for an internal ‘bladder’ to be reconstructed using a portion of the patient’s own intestine. This allows the patient to control when to empty the new ‘bladder’ and eliminates the need for an external bag, which may significantly improve a patient’s quality of life.” Dr. Singh shares.
As is the case with many other types of cancer, the earlier bladder cancer is detected, the better the outlook. The relative survival rates of bladder cancer provide a fairly positive prognosis for those whose cancer has not yet spread outside the bladder – about 70%. This further highlights the importance of being proactive about seeing a doctor and following up when symptoms persist. “If I see a patient who has blood in the urine, frequent urinary tract infections, or even persistent painful urination despite antibiotics, then I usually suggest referral to a urologist for further testing,” Dr. Holland says.
If you notice urinary symptoms, don’t just wait for them to go away – getting them checked out might save your life.
Derek Holland, MD
Medical Oncologist, Tennessee Oncology
Amar Singh, MD
Urological Oncologist, Erlanger Urology
