Bladder Cancer: Diagnosis

Approved by the Cancer.Net Editorial Board, 12/2021

ON THIS PAGE: You will find a list of common tests, procedures, and scans that doctors use to find the cause of a medical problem. Use the menu to see other pages.

Doctors use many tests to find, or diagnose, cancer. They also do tests to learn if cancer has spread to another part of the body from where it started. If the cancer has spread, it is called metastasis. Doctors may also do tests to learn which treatments could work best.

For most types of cancer, a biopsy is the only sure way for the doctor to know if an area of the body has cancer. In a biopsy, the doctor takes a small sample of tissue for testing in a laboratory. If a biopsy is not possible, the doctor may suggest other tests that will help make a diagnosis.

How bladder cancer is diagnosed

There are many tests used for diagnosing bladder cancer. Not all tests described here will be used for every person. Your doctor may consider these factors when choosing a diagnostic test:

  • The type of cancer suspected

  • Your signs and symptoms

  • Your age and general health

  • The results of earlier medical tests

The earlier bladder cancer is found, the better the chance for successful treatment and cure. However, there is not yet a test accurate enough to screen the general population for bladder cancer, so most people are diagnosed with bladder cancer once they have symptoms. As a result, some people have more advanced (later stage) disease when the cancer is found. Still, most people are usually diagnosed with noninvasive bladder cancer (see Introduction).

The following tests may be used to diagnose and learn more about bladder cancer:

  • Urine tests. If your doctor has found any amount of blood in the urine, a urine cytology test can be ordered. Urine cytology often uses a random urine sample from normal urination to find out if the urine contains tumor cells. If a patient is undergoing a cystoscopy (see below), an additional test may be performed that involves rinsing the bladder and collecting the liquid through the cystoscope or through another small tube that is inserted into the urethra. The sample can be tested in a variety of ways. The most common way is to look at the cells under a microscope, called urinary cytology. There are other urine tests using molecular analysis that can be done to help find cancer, usually at the same time as urinary cytology.

  • Cystoscopy. Cystoscopy is the key diagnostic procedure for bladder cancer. It allows the doctor to see inside the body with a thin, lighted, flexible tube called a cystoscope. Flexible cystoscopy is performed in a doctor's office and does not require anesthesia, which is medication that blocks the awareness of pain. This short procedure can detect growths in the bladder and determine the need for a biopsy or surgery.

  • Biopsy/Transurethral resection of bladder tumor (TURBT). If abnormal tissue is found during a cystoscopy, the doctor will do a biopsy. A biopsy is the removal of a small amount of tissue for examination under a microscope. This surgical procedure is called a transurethral bladder tumor resection or TURBT.

    During a TURBT, the doctor removes the tumor and a sample of the bladder muscle near the tumor. The doctor can also decide to do additional biopsies of other parts of the bladder based on the results of the cystoscopy. Another procedure often done before completing a TURBT is called EUA (exam under anesthesia). In this procedure, the urologist evaluates the bladder to see if any masses can be felt. Any tissue sample removed during the TURBT is then analyzed by a pathologist. A pathologist is a doctor who specializes in interpreting laboratory tests and evaluating cells, tissues, and organs to diagnose disease.

    A TURBT is used to diagnose bladder cancer and find out the type of tumor, how deeply it has grown into the layers of the bladder, and identify any additional microscopic cancerous changes, called carcinoma in situ (CIS) (see Stages and Grades). A TURBT can also be used as a treatment for a non-muscle-invasive tumor (see Types of Treatment).

  • Genetic counseling. Some people may have genetic factors that increase their risk for bladder cancer, so speaking with a genetic counselor and developing a detailed family medical history can help identify your potential risk of cancer and that of people in your family, including extended family.

  • Biomarker testing of the tumor. Your doctor may recommend running laboratory tests on a tumor sample to identify specific genes, proteins, and other factors unique to the tumor. This may also be called molecular testing of the tumor. Results of these tests can help determine your treatment options, especially if the cancer has spread.

The following imaging tests may be used to find out if the bladder cancer has spread and to help with staging. Imaging tests show pictures of the inside of the body.

  • Computed tomography (CT or CAT) scan. A CT scan takes pictures of the inside of the body using x-rays taken from different angles. A computer combines these pictures into a detailed, 3-dimensional image that shows abnormalities or tumors. A CT scan can be used to measure the tumor’s size and to identify enlarged lymph nodes, which may indicate that cancer has spread. Sometimes, a special dye called a contrast medium is given before the scan to provide better detail on the image. This dye can be injected into a patient’s vein (intravenous) or given as a liquid to swallow. Before taking this test, patients should tell the staff giving this test if they are allergic to iodine or other contrast media. The intravenous contrast dye used in a CT scan can cause renal problems, so patients with any kind of kidney problems should tell the staff before the scan is done.

  • Magnetic resonance imaging (MRI). An MRI uses magnetic fields, not x-rays, to produce detailed images of the body. MRI can be used to measure the tumor’s size and to identify enlarged lymph nodes, which may indicate that cancer has spread. A special dye called a contrast medium is given before the scan to create a clearer picture. This dye is different from the one given for a CT scan (see above) and can be injected into a patient’s vein.

  • Bone scan. A bone scan uses a radioactive tracer to look at the inside of the bones. The amount of radiation in the tracer is too low to be harmful. The tracer is injected into a patient’s vein. It collects in areas of the bone and is detected by a special camera. Healthy bone appears lighter to the camera, and areas of injury, such as those caused by cancer, stand out on the image. A bone scan may be recommended if there are specific symptoms or particular laboratory findings.

  • Positron emission tomography (PET) or PET-CT scan. A PET scan is usually combined with a CT scan (see above), called a PET-CT scan. However, you may hear your doctor refer to this procedure just as a PET scan. A PET scan is a way to create pictures of organs and tissues inside the body. A small amount of a radioactive substance is injected into the patient’s body. This substance is taken up by cells that use the most energy. Because cancer tends to use energy actively, it absorbs more of the radioactive substance. However, the amount of radiation in the substance is too low to be harmful. A scanner then detects this substance to produce images of the inside of the body.

    Ongoing research suggests that, in specific situations, a PET scan may possibly be better than a CT scan or MRI alone at helping to find bladder cancer that has spread. Despite this, PET scans are not considered standard imaging for bladder cancer and are not commonly used for this disease.

  • Ultrasound. An ultrasound uses sound waves to create a picture of the internal organs. It can help find out if the kidneys or ureters are blocked. This test does not require any type of contrast medium.

After diagnostic tests are done, your doctor will review the results with you. If the diagnosis is cancer, these results also help the doctor describe the cancer. This is called staging and grading.

The next section in this guide is Stages and Grades. It explains the systems doctors use to describe the extent of the disease and the way cancer cells look under a microscope. Use the menu to choose a different section to read in this guide.