Computed tomography (CT) scans are imaging tests that are very effective in detecting and monitoring bladder cancer.
Bladder cancer is a type of urinary tract cancer. It affects the bladder’s lining or muscle because of cells that develop abnormally.
Bladder cancer occurs more frequently in males. Symptoms can include:
- back pain
- pain while urinating
- frequent urinating
- blood in your urine
It’s important to diagnose and treat bladder cancer as soon as possible to prevent cancer cells from spreading.
CT scans are useful in detecting bladder cancer. They are widely available and are the most common method for detecting bladder and other urinary cancers. A doctor can use them to diagnose the cancer’s stage and to monitor the condition over time.
A CT scan conducts many X-rays to capture a cross-section of your body. It can detect soft tissues and blood vessels. A computer then uses the X-rays to create a three-dimensional image of your urinary tract area for a doctor to analyze.
A doctor may also use a CT scan to take a sample of, or biopsy, your bladder to collect cells for lab tests.
CT scans are very effective at detecting urinary tract cancers. A 2018 study found that CT urographies had a
One 2021 retrospective review found a 96% to 97% accuracy rate for CT scans detecting upper tract urothelial cancer, a type of cancer in the tubes that link the kidneys and bladder.
A CT scan is an outpatient procedure. It will not require a lot of preparation or recovery.
Ask your doctor how to prepare before your appointment. You may need to have a full bladder.
To begin your appointment, you may need to:
- complete paperwork
- ask questions
- change into a hospital gown
- remove any jewelry and other metal
Before the procedure
A healthcare professional will inject contrast dye into your arm with a thin tube. The tube will remain there throughout the scan. This dye helps the scan pick up better images of your soft tissues.
Brief symptoms of the contrast dye include:
- flushing sensation
- metallic taste
- urge to urinate
During the procedure
The scan will occur in a room with a tube-like machine. The machine has an attached bed that can move in and out of it. The scan should last around 30 minutes. The machine will generate a buzzing or whirring sound while in use.
During the scan, the CT scan technician will:
- position you on the bed, possibly with foam objects
- move you into the tube
- leave the room to avoid radiation exposure
- begin the scan
- reposition your bed during the scan, but you will remain still and hold your breath at times based on their instructions
After the procedure
The technician will come back into the room and remove the tube in your arm. They may ask you to remain in the office following the scan to make sure you don’t have a reaction to the dye. Once cleared, you can return to your normal activities.
You will receive scan results from your doctor a few days or weeks later.
You may not be eligible for a CT scan if you are pregnant.
Risks and side effects associated with CT scans include:
- allergic reaction to the dye
- reaction in your kidneys to the dye
- radiation exposure
- soreness, bruising, and swelling in your arm from the insertion of the dye
- complications from medications for diabetes or blood thinners
A CT scan can examine your kidneys, bladder, and the tubes that connect these organs. It can detect tumors, showing their size, shape, and position.
CT scans can also capture the lymph nodes in your abdomen and pelvis to see whether they have changed.
- X-ray: You may need a stand-alone X-ray to determine whether cancer has spread into other parts of your body.
- Ultrasound: An ultrasound uses sound waves to see inside your body without radiation. It may be used if you need a bladder biopsy.
- MRI: A pelvis MRI scan examines the soft tissues with radio waves and magnets instead of X-rays. It may be an even more accurate way to detect stages of bladder cancer than a CT scan. You may not be eligible for an MRI if you have any metal or other foreign objects in your body.
- Intravenous pyelogram: This is an X-ray of your urinary system that occurs while your urinary system processes a dye injected into your veins through your arm.
- Retrograde pyelogram: A retrograde pyelogram is an X-ray of your urinary system after you receive dye administered via a catheter into your urethra.
You may have questions about a CT scan and bladder cancer. These can include how effective they are and the best way to diagnose bladder cancer.
How often does a CT scan miss bladder cancer?
Most of the time, CT scans are very accurate, though false negatives and false positives can happen.
Researchers in the same study also found 43 false positives in 710 CT scans for people who had blood in their urine or a history of bladder cancer. Some false positives were attributed to:
- a harmless enlarged prostate (in males)
- a naturally thickening bladder
- changes to medical treatment
- the presence of blood clots
What is the best test to diagnose bladder cancer?
There are many tests available to detect bladder cancer. CT scans and MRIs are useful imaging tools to diagnose and monitor bladder cancer. Other non-radiation tests include:
- urine tests
CT scans are a useful tool to diagnose and monitor bladder cancer. They are minimally invasive and performed as an outpatient procedure.
Your doctor may begin with non-radiation tests and then order a CT scan to gather additional information about potential bladder cancer. You may also receive CT scans during treatment to monitor the condition.