Bladder cancer can sometimes be detected at an earlier stage because it may cause noticeable changes in urination. The most common warning sign is blood in the urine, medically called hematuria. Other possible symptoms include frequent urination, an urgent need to urinate, burning or pain during urination, difficulty urinating, and a weak urine stream.
Bladder cancer develops when cells in the bladder begin growing abnormally and without normal control.
The bladder is a muscular organ in the lower abdomen that stores urine produced by the kidneys. Urine travels from the kidneys through the ureters into the bladder and eventually leaves the body through the urethra.
Most bladder cancers begin in urothelial cells, which line the inside of the bladder and parts of the urinary tract. The NCI describes urothelial carcinoma as the most common type of bladder cancer.
Bladder cancer can be classified according to how deeply it has grown into the bladder wall. Some cancers remain within the inner lining and are considered non-muscle-invasive, while others grow into the muscle layer or beyond.
Blood in the urine is the most common symptom associated with bladder cancer.
The urine may appear:
However, blood may not always be visible. Small amounts can only be detected through a urine test.
Bleeding may also come and go. A person might notice blood on one occasion and then have apparently normal urine afterward.
Early bladder cancer can cause bleeding with little or no pain, according to the American Cancer Society.
Blood in the urine should not automatically be attributed to cancer. Urinary infections, kidney stones, bladder stones, kidney disease, and other noncancerous conditions can also cause hematuria.
Nevertheless, unexplained blood in the urine warrants medical evaluation.
Needing to urinate more frequently than usual can be another urinary symptom associated with bladder cancer.
The change may involve making more trips to the bathroom during the day or waking repeatedly at night.
Frequent urination has many possible causes, including:
Because these causes are much more common than bladder cancer, frequency alone does not establish a cancer diagnosis.
Persistent or unexplained changes should still be evaluated by a healthcare professional.
Some people experience a sudden, strong urge to urinate.
The sensation may occur even when the bladder is not very full.
Urinary urgency can occur with bladder cancer, but it is also common with urinary infections and overactive bladder.
A pattern that is new, persistent, or accompanied by blood in the urine deserves medical attention.
Pain or burning while urinating is another possible symptom.
This sensation is often associated with a urinary tract infection, but bladder cancer can also cause bladder irritation and painful urination.
A urine test may help determine whether an infection is present. If symptoms continue or return without a clear explanation, further evaluation may be necessary.
Some bladder cancer patients may experience difficulty urinating or a weaker-than-usual urine stream.
This symptom can have several other causes.
For example, prostate enlargement can interfere with urine flow in men. A urethral narrowing, bladder dysfunction, certain medications, or neurological conditions can also contribute.
The American Cancer Society lists difficulty urinating and a weak urine stream among possible bladder cancer symptoms.
Repeated nighttime urination, sometimes called nocturia, can occur with bladder cancer.
However, nocturia is common for many other reasons, particularly with increasing age.
Potential causes include:
Nighttime urination by itself is therefore not a specific indicator of bladder cancer.
Bladder cancer can sometimes cause discomfort in the lower abdomen or pelvic region.
Pelvic discomfort can also have numerous other causes, including urinary infections, reproductive-system conditions, gastrointestinal problems, and muscle-related conditions.
Persistent unexplained pelvic symptoms should be assessed medically.
Lower back pain can occur with bladder cancer, particularly when disease has become more advanced.
The American Cancer Society notes that lower back pain on one side can occur with bladder cancer that has grown larger or spread.
Most lower back pain is not caused by bladder cancer. Muscle strain, arthritis, disc problems, kidney stones, and many other conditions are much more common causes.
Back pain combined with urinary changes or blood in the urine should receive appropriate medical attention.
Early bladder cancer often produces urinary symptoms rather than widespread symptoms.
When bladder cancer becomes larger or spreads beyond the bladder, additional symptoms can occur.
These may include:
The NCI and American Cancer Society both describe these symptoms in the context of more advanced disease.
These symptoms can also have causes unrelated to cancer.
Blood in the urine is particularly important because it can sometimes be the first noticeable indication of bladder cancer.
The blood may be visible or microscopic.
Visible blood can change the color of urine, while microscopic hematuria may only be detected through laboratory testing.
A single episode can disappear, but that does not necessarily mean the underlying cause has disappeared.
The American Cancer Society notes that blood in the urine is often caused by conditions other than bladder cancer, but evaluation is still important.
One reason bladder cancer can be difficult to recognize from symptoms alone is that several warning signs overlap with urinary tract infections.
Both conditions can cause:
A urine test can help identify an infection.
If urinary symptoms persist after treatment for an infection, repeatedly return, or occur alongside unexplained blood in the urine, additional evaluation may be appropriate.
The American Cancer Society specifically notes that urinary infections and bladder cancer can produce similar symptoms.
Several factors can increase bladder cancer risk.
Smoking is the most important known risk factor for bladder cancer, according to the CDC.
Chemicals from tobacco smoke can enter the bloodstream and eventually be filtered by the kidneys into urine, exposing the bladder lining to potentially harmful substances.
Certain occupational chemical exposures can increase risk.
The CDC identifies exposure to chemicals used in industries involving paint, dyes, metals, petroleum products, and related materials as a risk factor.
A previous diagnosis of bladder cancer increases the possibility of recurrence.
People who have already been treated for bladder cancer may therefore undergo periodic follow-up testing.
A family history of bladder cancer can be associated with increased risk.
Certain genetic changes can also influence risk, although most cases are not explained by a single inherited genetic mutation.
Some chemotherapy drugs, certain chronic urinary conditions, and particular environmental exposures have also been associated with bladder cancer risk.
Risk depends on the combination of factors rather than one symptom or exposure alone.
For people at average risk who have no symptoms, there is currently no standard routine screening test for bladder cancer.
The NCI states that evidence has not established a standard screening test that reduces bladder cancer mortality in average-risk populations.
Certain people at substantially increased risk may receive individualized evaluation.
Testing can also be performed when symptoms such as blood in the urine occur.
This distinction is important: investigating a symptom is different from routine screening in someone without symptoms.
A diagnosis cannot be made from symptoms alone.
A healthcare professional may begin with a medical history, physical examination, and urine testing.
Urinalysis can detect blood and other substances in urine.
It can also provide information that may point toward an infection or another urinary condition.
Urine cytology examines urine under a microscope to look for abnormal or cancerous cells.
It can detect some bladder cancers but does not identify every case.
When infection is suspected, a urine culture may be performed.
This can help determine whether bacteria are causing urinary symptoms.
Cystoscopy allows a healthcare professional to look directly inside the bladder and urethra.
A thin instrument called a cystoscope is inserted through the urethra into the bladder.
The NCI identifies cystoscopy as an important diagnostic procedure when bladder cancer is suspected.
If an abnormal area is identified, tissue may be removed for examination under a microscope.
A biopsy can determine whether cancer cells are present and can provide information about the characteristics of the tumor.
Depending on the circumstances, imaging studies may be used to evaluate the urinary tract and determine whether disease has extended beyond the bladder.
A primary care physician can initially evaluate urinary symptoms.
Depending on the findings, referral to a urologist may be appropriate.
A urologist specializes in conditions involving the urinary system and, in men, the male reproductive system.
If bladder cancer is diagnosed, additional specialists may become involved, including:
Treatment depends on the cancer type, grade, stage, overall health, and other individual factors.
Unexplained blood in the urine should receive medical evaluation, even if it occurs only once.
This is particularly important when there is no obvious explanation.
Blood in the urine does not automatically mean cancer, but it can be an early warning sign.
The American Cancer Society notes that blood may disappear and later return in people with bladder cancer, so the absence of bleeding on a later day does not necessarily resolve the issue.
Medical assessment is particularly important when urinary symptoms are:
Inability to urinate can require urgent medical care.
Severe symptoms after significant trauma or rapidly worsening neurological or urinary problems should also receive prompt evaluation.
Not every case of bladder cancer can be prevented.
However, some risk factors can be reduced.
The CDC identifies smoking cessation as an important way to lower bladder cancer risk. Appropriate precautions around occupational chemicals can also reduce exposure to potentially harmful substances.
Regular medical care can also help identify concerning symptoms and investigate them appropriately.
Bladder cancer can sometimes be identified before it has spread beyond the bladder because urinary symptoms lead to medical evaluation.
The American Cancer Society notes that finding bladder cancer early, when it is small and has not spread, can improve treatment prospects.
There is an important distinction between early detection and routine screening.
For average-risk people without symptoms, routine bladder cancer screening is not currently recommended. When symptoms such as unexplained blood in the urine occur, however, diagnostic evaluation may be appropriate.