Bladder Mass: What a Mass in the Bladder Means

What a mass in the bladder means

The bladder is a hollow, muscular bag lined by a layer of cells called the urothelium. When a report says there is a "mass" in the bladder, it means a scan or camera has seen something that projects into the urine-filled space, or an area where the wall is thicker than it should be. Radiologists use related phrases:

A mass is a finding that needs explaining, not a diagnosis. Ultrasound and CT cannot reliably tell a tumor from a clot or a patch of inflammation, so almost everyone with a true bladder mass is offered a cystoscopy to look directly.

Causes of a bladder mass

Bladder cancer

Most solid masses that persist on cystoscopy in adults turn out to be bladder cancer. More than 90% of bladder cancers in the US are urothelial carcinomas (also called transitional cell carcinomas). About 3 in 4 are found while they are still confined to the lining (non-muscle-invasive), which makes them very treatable.

Clues that point toward cancer:

• age over 50 and especially over 70
• smoking, now or in the past, which is the single biggest risk factor
• painless, visible blood in the urine
• work exposure to dyes, rubber, leather, paint or diesel exhaust (aromatic amines)
• previous pelvic radiotherapy or the chemotherapy drug cyclophosphamide
• long-term catheters or chronic infection with the parasite Schistosoma (linked to squamous cell carcinoma)

Less common bladder cancers include squamous cell carcinoma, adenocarcinoma (which can arise from the urachus at the dome of the bladder) and small cell carcinoma. Cancers from nearby organs, such as the prostate, cervix, uterus or colon, can also grow into the bladder.

Benign causes that look like a mass

Other rare benign causes include malakoplakia, eosinophilic cystitis, paraganglioma, fungus balls in people with diabetes or weak immunity, and amyloid deposits.

Wall thickening from obstruction

When the bladder has to push against a blockage, such as an enlarged prostate or a narrowed urethra, its muscle thickens all over. This is called trabeculation. It is diffuse rather than a single lump, but it can be reported as "thickening" and needs to be distinguished from cancer by cystoscopy if one area stands out.

Symptoms of a bladder mass

Many bladder masses cause no symptoms and are found by chance on a scan. When symptoms occur they include:

• Blood in the urine (hematuria): the most common sign of bladder cancer. It is usually painless and may come and go, so it can disappear for weeks. Pink, red or cola-colored urine, or blood found only on a dipstick test, both count.
• Irritation symptoms: needing to pass urine often, urgency or burning, without an infection on testing. These are typical of carcinoma in situ, a flat, high-grade form of early bladder cancer.
• Trouble passing urine: a weak stream or a feeling of incomplete emptying, if the mass sits near the outlet.
• Pain: usually a late sign. Pain in the lower belly, pelvis, side or bone pain can mean a more advanced tumor or a blocked kidney.
• General symptoms: unexplained weight loss, tiredness or leg swelling suggest advanced disease.

Benign bladder mass symptoms

Benign masses often produce the same symptoms, which is why symptoms alone cannot settle the question. Stones tend to cause pain at the tip of the penis or in the lower belly, interrupted flow and blood after exercise. Inflammatory masses usually come with recurrent infections or a burning feeling. Endometriosis causes cyclical pain and bleeding. A clot follows a recent bleed.

How doctors rule out a bladder mass

If blood in the urine or a scan raises concern, a urologist follows a fairly standard workup.

1. Questions: smoking history, work exposures, how the blood looked and when, infections, stones, medicines (such as blood thinners), periods and any pelvic radiation.
2. Urine tests: a dipstick and microscope to confirm blood, a culture to exclude infection, and sometimes urine cytology, which looks for cancer cells. Cytology is good at catching high-grade tumors but misses many low-grade ones.
3. Imaging: a CT urogram (CT with contrast and delayed images) checks the kidneys, ureters and bladder. Ultrasound is used for lower-risk people or those who cannot have contrast. MRI helps judge how deeply a tumor has grown.
4. Cystoscopy: a thin camera is passed through the urethra into the bladder, usually under local anesthetic gel in the clinic. It takes about 5 minutes. A flexible scope shows exactly where the mass is, what it looks like and whether there are others.
5. TURBT (transurethral resection of bladder tumor): if a growth is seen, it is removed under anesthesia through the urethra with no skin cut. The tissue goes to a pathologist, who says what it is, its grade, and whether it has grown into the muscle layer.

What happens if it is cancer

Treatment depends on the stage and grade:

• Non-muscle-invasive bladder cancer: TURBT removes the tumor. Many people then have a single dose of chemotherapy into the bladder, and higher-risk tumors are treated with a course of BCG, a weakened bacteria placed into the bladder to stimulate the immune system. Regular check cystoscopies are needed, because these tumors often come back.
• Muscle-invasive bladder cancer: usually treated with chemotherapy followed by removal of the bladder (radical cystectomy) and a new way to store or drain urine, or with combined chemotherapy and radiotherapy that keeps the bladder.
• Advanced cancer: chemotherapy, immunotherapy and targeted drugs such as antibody-drug conjugates.

Caught early, non-muscle-invasive bladder cancer has a five-year survival rate well above 90%.

Treatment of benign bladder masses

• Clots: a catheter with bladder washouts, and treatment of the bleeding source.
• Stones: broken up with a laser through a cystoscope (cystolitholapaxy), plus treatment of whatever stops the bladder emptying.
• Inflammatory lesions: treating infection and removing irritants such as a long-term catheter. Some are removed to confirm the diagnosis.
• Benign tumors: removed through the urethra, or by surgery for larger leiomyomas.
• Endometriosis: hormonal treatment or surgery, often with a gynecologist and urologist together.

Lowering your risk

Stopping smoking cuts bladder cancer risk substantially over time, though it takes years to approach that of a non-smoker. Follow workplace safety rules if you handle industrial chemicals. Drink enough fluid to keep your urine pale, and get any visible blood in the urine checked promptly rather than waiting to see if it returns.

Frequently asked questions

What does a mass in the bladder mean?

It means a scan or camera has seen a growth, lump or thickened area inside the bladder. It could be cancer, but it could also be a clot, stone, inflammation, a benign polyp or an enlarged prostate bulging into the bladder. A cystoscopy, often with removal or biopsy of the mass, is needed to know which.

Is a bladder mass always cancer?

No. Many bladder findings on ultrasound or CT turn out to be benign, such as clots, stones, debris or wall thickening from an enlarged prostate. However, a persistent solid growth seen on cystoscopy in an adult over 50 is often cancer, so it should always be removed or biopsied.

What are the symptoms of a benign bladder mass?

Benign masses can cause blood in the urine, frequent or urgent urination, burning, a weak stream or lower belly discomfort. Stones often cause pain and interrupted flow, and inflammatory lesions come with repeated infections. Because cancer causes the same symptoms, tests rather than symptoms decide whether a mass is benign.

Can a bladder mass be seen on ultrasound?

Yes, masses larger than about 5 mm are often visible, especially when the bladder is full. Ultrasound can miss small or flat tumors and cannot reliably tell a tumor from a clot or inflammation. That is why cystoscopy remains the standard test when there is blood in the urine.

How is a mass in the bladder removed?

Most are removed by TURBT. Under general or spinal anesthesia, a surgeon passes a scope through the urethra and shaves the growth away with an electric loop. There is no external cut, most people go home the same day or the next, and the tissue is sent for diagnosis.

How quickly do I need to be seen for a bladder mass?

A newly found bladder mass, or visible blood in the urine in an adult, should be assessed by a urologist within a few weeks. In the US and UK this is treated as an urgent referral. Go to the ER sooner if you cannot pass urine or are bleeding heavily with clots.