A bladder is an organ situated in the pelvis that functions as a storehouse for urine before its discharged from the body. The bladder considered one of the vital organs of the urinary tract along with the uterus, urethra, and the kidney.

The bladder is lined by a cellular layer collectively known as the urothelium. The muscular wall of the bladder is referred to as the muscularis propria. Bladder cancer is caused when these cells of the bladder, particularly the urothelial cells, grow and divide uncontrollably to form abnormal cells or a mass, or tumor.

Bladder cancer occurs in several different types, which much be diagnosed by taking a small sample of tumor cells and examining them in a laboratory:

1. Urothelial carcinoma

This is the most common type of bladder carcinoma accounting for 90% of bladder cancer patients. As the name suggests, this cancer initiates in the urothelial cells of the urinary tract. This type of carcinoma is also called the transitional carcinoma or TCC.

2. Squamous carcinoma

This second type of bladder cancer develops in the squamous cell, as the cells become inflamed. This carcinoma is less common and occurs in only 4% of patients with bladder cancer.

3. Adenocarcinoma

Only 2% of bladder cancer patients develop adenocarcinoma, a type of cancer that begins in the glandular cells of the urinary tract.

4. Sarcoma

Sarcoma is the least common type of urinary cancer that develops in the fat layer of the urinary bladder.

5. Anaplastic cancer

This type of bladder cancer grows in of the small cells and spreads from the bladder to the other parts of the body.

Stages of Bladder Cancer

Bladder cancer staging is conducted by doctors in order to classify the characteristics of the tumor cells. They generally follow the TNM classification to determine the stage. These stages are as follows:

• Stage I: This is the cancerous stage where the cells of the bladder inner lining grow to reach the lamina propria. In this stage, the cells proliferation is restricted to the local site and do not spread to the bladder muscular wall.
• Stage II: In this stage, the cancerous cells progressively grow to enter into the muscular layers of the bladder. Al this stage this is also termed as muscle invasive carcinoma. The tumor cells at this stage do not enter the surrounding fatty layers.
• Stage III: In this stage, the tumor cells reach the muscle wall and the fatty tissue called the perivesical tissue of the bladder. In this stage, the bladder cancer treatment begins as the symptoms become clear and graver. This stage (Stage IIIA) cancer spread to the uterus, vagina and the prostate. In this stage (Stage IIIB) the symptoms become graver and spread to the regional lymphatic systems.
• Stage IV: This is the last stage where cancer affects distant organ beyond the pelvic regions. In the initial stage (Stage IVA) cancer becomes more common in the abdominal region which progresses to other parts of the body (Stage IVB).