Most bladder cancers are urothelial carcinomas. But some rarer types, like squamous cell carcinoma and sarcoma, are more aggressive and require different treatments.

Bladder cancer happens when cancerous cells grow in the tissues of the bladder, where urine is stored until you pee.

Several types of bladder cancers affect different tissues in the bladder. This means you may experience different symptoms and need different treatments depending on the type of bladder cancer you have and what stage it’s in.

Read on to learn more about the types of bladder cancer, what symptoms and treatments are used for each type, and how a healthcare professional can determine what type you have.

Almost all bladder cancers (9 out of 10) are urothelial carcinomas. Also called transitional cell carcinoma, this type of cancer happens when cancer cells start growing in the transitional cells that make up your bladder’s inner layer. Transitional cells help your bladder stretch when it fills up with urine so that it isn’t damaged when it stretches.

Some symptoms include:

Treatment for urothelial carcinoma may include:

Squamous cells are thin cells along the inside of the bladder. Squamous cell carcinoma happens when long-term bladder infections damage or irritate these cells. Such infections are often due to parasitic worms that can cause a condition called schistosomiasis (or bilharzia).

Symptoms of squamous cell carcinoma include:

  • blood in your pee
  • aching back pain that doesn’t get better over time
  • peeing a lot more than usual
  • pain or burning when you pee
  • feeling like you have to pee urgently, but nothing comes out

Treatment for squamous cell carcinoma may include:

  • surgery to remove cancerous cells
  • chemotherapy
  • surgery to remove the bladder (cystectomy) and nearby lymph nodes (for advanced stages)

Adenocarcinoma happens when cancer cells grow in gland-like, mucus-producing cells in the lining of your bladder. You have many of these gland-like epithelial cells throughout your body. This type of cancer usually happens when inflammation in your bladder causes damage or irritation to these epithelial cells.

Adenocarcinomas are a rare form of bladder cancer, making up less than 2% of all bladder cancer cases.

Symptoms of adenocarcinoma in the bladder are similar to those of other types of bladder cancer, especially blood in the pee, back pain, and burning when you pee.

Treatments for bladder adenocarcinoma include chemotherapy and cystectomy.

Small cell carcinoma happens in bladder cells called neuroendocrine cells that receive signals from your nervous system and produce hormones that go into your bloodstream.

It’s a very rare form of bladder cancer, making up less than 1% of cases.

Symptoms of small cell carcinoma in the bladder include:

Treatments for this type of bladder cancer include:

  • removal of the bladder
  • chemotherapy
  • radiotherapy

Sarcomatoid carcinoma (or sarcoma) in the bladder happens when cancer cells grow in the transitional urothelial cells and other tissues where sarcomas can develop, such as the bone and other connective tissues.

It’s an extremely rare type of bladder cancer. Scientists have documented fewer than 100 cases of bladder sarcomas.

Symptoms of bladder sarcoma include:

Because this type of bladder cancer is so rare, there’s no typical treatment plan for it. But if it’s advanced, doctors may need to remove your bladder and the surrounding tissues or lymph nodes. They may also recommend chemotherapy.

Muscle-invasive vs. non-muscle-invasive bladder cancer

Non-muscle-invasive bladder cancer hasn’t spread deeply into the layers of the bladder or nearby muscles. About 70% of bladder cancers are non-muscle-invasive.

Muscle-invasive bladder cancer has spread deeper into these muscles compared with non-muscle-invasive bladder cancer.

Some types of bladder cancer don’t spread into the muscle. Other types might spread into the muscle as they advance to further stages and start to metastasize in other tissues around the bladder.

Some tests to determine the type of bladder cancer you have include:

  • cystoscopy to look inside your bladder and see what tissues are affected
  • urine cytology to examine microscopic bladder cells and how cancer might be affecting them
  • biopsy to analyze tumors for the presence of cancer cells and examine what bladder cells are affected
  • imaging tests like a computed tomography (CT) scan or intravenous pyelogram (IVP) for detailed images of the inside of your bladder
  • a urine tumor marker test to detect the presence of specific types of cancer cells

Here are some of the most frequently asked questions about bladder cancer types.

What is the most common type of bladder cancer?

Urothelial carcinoma is, by far, the most common type of bladder cancer. This type of cancer can also affect your kidneys and the ureters that connect your kidneys to your bladder.

What is the most aggressive type of bladder cancer?

Sarcoma is the most aggressive type of bladder cancer, but it’s also the most rare. A 2022 study confirmed that sarcomas were more aggressive than urothelial carcinomas and adenocarcinomas, but found they had similar survival rates to squamous cell carcinomas.

What percentage of bladder tumors are cancerous?

Bladder tumors are almost always cancerous, but in some cases can be benign lesions, such as hemangioma or a fungal infection.

A tumor biopsy is the best way to confirm the presence of cancerous cells.

There are several types of bladder cancer with slightly different symptoms and treatments. Most bladder cancers are urothelial (transitional cell) carcinomas, but some rarer subtypes may be more aggressive and require different treatment approaches.

Talk with a healthcare professional if you’re concerned about bladder cancer and how the type you have may affect your treatment plan.