Your bladder is a balloon-shaped organ that sits between your chest and pelvis. Your body uses the bladder to store urine until you empty it by urinating. The bladder is made of three sets of muscles that work together to keep urine inside until you urinate: urethra, internal sphincter, and external sphincter. When you urinate, your brain sends signals to your bladder wall to squeeze urine out and to your external sphincters to release urine through the urethra.

Non-invasive bladder cancers only exist in the transitional epithelium (the inner lining of the bladder) and have not spread to the deeper layers of the bladder. Invasive bladder cancers have grown into the layers of the bladder wall, are more likely to spread, and are difficult to treat.

Urothelial carcinoma is the most common type of bladder cancer. It develops in the cells of the urothelium and can form tumors called papillary carcinomas. Squamous cell carcinoma is a type of bladder cancer that is caused by a chronic bladder infection, such as long-term use of a urinary catheter. Squamous cell carcinoma is not common in the United States, but it can be found in countries where a parasite infection called schistosomiasis is common.

Adenocarcinoma is another form of bladder cancer that is rare in the United States. It begins in gland-forming cells that line the bladder and release mucus into the bladder. Most adenocarcinomas in the bladder are invasive.

Papillary carcinomas are tumors that look like little fingers on the inner lining of the bladder. They grow from the lining toward the center of the bladder. Flat carcinomas, also called non-invasive flat carcinomas or flat carcinoma in situ, are tumors that are contained in the inner lining of the bladder. They do not grow toward the center of the bladder.

Bladder cancer staging is a method that doctors use to determine how aggressive bladder cancer is and how far it has spread. It is one of the most important techniques used to determine how to treat your bladder cancer. Stages range from 0 to 4 and can also include letters that give more information. A low number means the cancer is in an early stage while a higher number means that the cancer is more advanced.

Intravesical immunotherapy and immune checkpoint inhibitors force the body to attack its own cancer cells. During intravesical immunotherapy, a live germ is placed inside the bladder through a catheter. When the body reacts by attacking the germ in the bladder, it also kills the bladder cancer cells. Injections of immune checkpoint inhibitors help the immune system differentiate the cells that are healthy from the cells that are harmful and then attack the harmful cells.

Chemotherapy is a drug that kills cancer cells. During systemic chemotherapy, people either take the chemotherapy in the form of a pill, or the chemotherapy is injected into the vein or muscles. This allows the chemotherapy to reach cancer cells that are in other parts of the body as well as the bladder. During intravesical chemotherapy, a doctor inserts a liquid chemotherapy drug directly into the bladder that kills cancer cells that are only in the inner lining of the bladder.

Transurethral resection of the bladder (TURBT) is a surgical procedure that is performed to determine if a person has bladder cancer and whether it has spread to the muscle of the bladder wall. It is also done to treat early stage bladder cancer. TURBT is a noninvasive procedure. The surgeon inserts a thin tube with a camera, light, and wire loop on the end into the urethra and uses it to remove cancerous tumors and tissues that are sent to the lab for testing.

A cystectomy surgical procedure involves the surgeon removing part (partial cystectomy) or all (radical cystectomy) of the bladder. Men who have this procedure also have their prostate and seminal vesicles removed while women also have their fallopian tubes, uterus, cervix, and a part of their vagina removed. People who undergo radical cystectomy must also have reconstructive surgery so that their bodies have another way to store and release urine.

During radiation therapy, doctors aim radiation beams, a process called external beam radiation therapy, at an area outside of your body. In some cases, radiation therapy is combined with chemotherapy. This is called chemoradiation.