Urothelial carcinoma is a cancer that starts in the urothelium, the specialized lining that covers the inside surface of the urinary tract. It accounts for roughly 90% of all bladder cancers and is one of the most common cancers overall, with an estimated 84,530 new cases expected in the United States in 2026. As of 2023, more than 763,000 Americans were living with bladder cancer.
Where Urothelial Carcinoma Develops
The urothelium (sometimes called transitional cell epithelium) lines nearly the entire urinary tract, from the renal pelvis inside each kidney, down through the ureters, across the bladder, and into the upper portion of the urethra. Because these cells exist along the whole pathway, urothelial carcinoma can technically form anywhere urine travels. The bladder is by far the most common site, but the same cancer can appear in the upper urinary tract as well.
Common Symptoms
About 80% of people with urothelial carcinoma first notice blood in their urine. This is typically painless and comes and goes, which can lead people to assume the problem resolved on its own. Sometimes the blood is visible to the naked eye, turning urine pink, red, or brownish. Other times it is only detectable under a microscope during a routine urinalysis.
Roughly 20% of patients present with irritative urinary symptoms instead: a burning sensation while urinating, sudden urgency, needing to go more frequently, or difficulty holding urine. In more advanced cases, symptoms can include flank pain from a blocked ureter, abdominal pain, or swelling in the legs caused by pressure on blood vessels in the pelvis.
Risk Factors
Smoking is the single largest risk factor, responsible for roughly half of all bladder cancer cases. The chemicals absorbed from tobacco are filtered by the kidneys and concentrate in the urine, where they sit in direct contact with the urothelium for hours at a time.
Occupational exposure to certain chemicals also plays a significant role. Workers exposed to ortho-toluidine, a compound used in dye manufacturing, face a risk roughly two to seven times higher than the general population. Dry cleaners exposed to tetrachloroethylene for more than ten years have about a 57% higher risk. Hairdressers, painters, and petroleum industry workers all show elevated rates as well. Pesticide exposure carries a moderate level of evidence as a risk factor, with landscape and horticultural workers showing roughly 2.4 times the risk in one study, increasing with years on the job.
Age is another major factor. Most diagnoses occur after age 55, and men are diagnosed about three to four times more often than women.
How It Is Diagnosed
The primary diagnostic tool is cystoscopy, a procedure where a thin camera is passed through the urethra into the bladder. It gives doctors a direct view of the bladder lining and allows them to take tissue samples from anything suspicious. Cystoscopy is highly accurate: studies report sensitivity ranging from 87% to 100% and negative predictive values between 98% and 100%, meaning a normal result is very reliable at ruling out cancer.
Urine cytology, which examines a urine sample under a microscope for abnormal cells, is often used alongside cystoscopy. It is particularly good at detecting high-grade cancers but less reliable for low-grade tumors. Imaging scans of the upper urinary tract, typically a CT scan with contrast dye, help determine whether cancer exists in the ureters or kidneys.
Staging and What It Means
Staging describes how far the cancer has grown, and it drives almost every treatment decision. The system uses T, N, and M categories.
The T category reflects how deeply the tumor has invaded the bladder wall. At the earliest stages (Ta and Tis), cancer sits only in the innermost lining and has not penetrated deeper tissue. T1 means it has grown into the connective tissue beneath the lining but not yet into muscle. T2 tumors have reached the muscle layer of the bladder wall. T3 means the cancer has pushed through the muscle into the surrounding fat. T4 indicates it has spread into nearby organs like the prostate, uterus, vagina, or the pelvic wall itself.
The distinction between non-muscle-invasive disease (Ta, Tis, T1) and muscle-invasive disease (T2 and beyond) is the most important dividing line in treatment. Roughly 75% of new diagnoses are non-muscle-invasive, which carries a much better prognosis but a high tendency to recur.
N categories describe whether cancer has reached nearby lymph nodes, and M categories indicate whether it has spread to distant organs such as the lungs, liver, or bones.
Treatment for Non-Muscle-Invasive Disease
When the cancer is confined to the bladder lining, the first step is a procedure called transurethral resection, where the tumor is scraped or cut away through a scope inserted via the urethra. This is done under anesthesia and typically does not require a large incision.
For intermediate and high-risk tumors, the standard follow-up is BCG therapy, where a weakened form of a tuberculosis-related bacterium is instilled directly into the bladder through a catheter. The solution triggers an immune response that attacks remaining cancer cells along the bladder lining. The standard schedule begins with six weekly instillations, followed by a maintenance phase of three weekly instillations repeated at months 3, 6, 12, 18, 24, 30, and 36. For high-risk tumors, the full three-year maintenance schedule is more effective at preventing recurrence than stopping at one year.
Because non-muscle-invasive urothelial carcinoma recurs frequently, regular surveillance cystoscopies are necessary for years after treatment, often every three to six months initially and then at longer intervals.
Treatment for Muscle-Invasive Disease
When cancer has grown into the muscle wall, the standard treatment is surgical removal of the entire bladder, called radical cystectomy. In men, this typically includes removing the prostate. In women, it may include removal of the uterus and part of the vagina. Chemotherapy is generally given before surgery to shrink the tumor and improve outcomes.
Life After Bladder Removal
After the bladder is removed, urine needs a new exit route. The two most common options are an ileal conduit and a neobladder.
An ileal conduit is the simpler procedure. A short segment of intestine is used to create a channel that connects the ureters to an opening (stoma) on the abdomen. Urine drains continuously into a small external pouch worn against the skin. The operation is shorter and carries fewer immediate complications, making it a common choice for older patients or those with other health conditions. Over time, however, stomal complications occur in about 24% of patients, and parastomal hernias develop in 30% to 50% of cases within a few years.
A neobladder is a more complex reconstruction where a larger piece of intestine is shaped into a reservoir and connected to the urethra, allowing you to urinate in a more natural way. Daytime continence reaches roughly 90%, though nighttime continence is closer to 70%. This option is not suitable for everyone. It requires adequate kidney function, no cancer involvement of the urethra, and the physical and cognitive ability to perform self-catheterization if the new bladder does not empty completely. Both options require lifelong monitoring for metabolic changes, since intestinal tissue reabsorbs substances from urine that the body normally excretes.
Treatment for Advanced or Metastatic Disease
When urothelial carcinoma has spread beyond the bladder, treatment focuses on systemic therapies that reach cancer cells throughout the body. Platinum-based chemotherapy has been the longstanding first-line approach, but newer treatments have significantly changed the landscape.
Immunotherapy drugs that block a protein called PD-1 help the immune system recognize and attack cancer cells. These are approved for patients whose disease has progressed during or after platinum-based chemotherapy, with objective response rates around 20%.
A major advance came from combining an antibody-drug conjugate with immunotherapy as a first-line treatment. The antibody-drug conjugate works by targeting a protein called nectin-4, which sits on the surface of most urothelial cancer cells. Once the drug locks onto this protein, it gets pulled inside the cell and releases a compound that destroys the cell from within. In a landmark clinical trial (EV-302), this combination nearly doubled median overall survival compared to standard chemotherapy: 31.5 months versus 16.1 months. Progression-free survival also doubled, from 6.3 months to 12.5 months, and the overall response rate reached 67.7% compared to 44.4% with chemotherapy alone.
Outlook and Recurrence
Prognosis varies dramatically by stage. Bladder cancer caught at a localized stage, before it invades the muscle wall, has a five-year relative survival rate above 95%. Once it reaches the muscle or nearby lymph nodes, that rate drops substantially. Distant metastatic disease carries a five-year survival rate in the range of 5% to 10%, though newer combination therapies are beginning to shift those numbers upward.
One defining characteristic of urothelial carcinoma is its tendency to come back. Even after successful treatment of early-stage disease, recurrence rates range from 30% to 80% depending on tumor grade, size, and number of tumors present. This is why long-term follow-up with repeated cystoscopies is considered essential rather than optional. The high recurrence rate makes bladder cancer one of the most expensive cancers to treat on a per-patient, lifetime basis, largely because of the extended surveillance required.