"Bladder cancer is a disease of the urinary bladder where malignant (cancer) cells form in the tissues of the bladder," according to doctors from the Urology Centre at Singapore General Hospital, a member of the SingHealth group. It is more common in men than women and occurs in older patients.

The bladder is a balloon-shaped organ in the lower part of the abdomen. It has a muscular wall that can distend with urine until it is emptied.

Bladder cancer is closely associated with the following risk factors:

1. Contact with certain chemicals that predispose to cancer formation. This may occur through:
   1. Smoking
   2. Occupational contact with aniline dyes in rubber, textile, paint, leather, metal and the hair dye industry
      
   3. Chemotherapy with cyclophosphamide
   4. Chronic intake of certain Chinese herbs and painkillers especially phenacetin
2. Smoking
3. Pelvic radiation for other cancers
4. Chronic bladder inflammation from untreated bladder stones, long-term in-dwelling catheter or infection by a specific bladder parasite

There are three subtypes of bladder cancer:

1. Transitional cell or urothelial carcinoma. Cancer that derives from transitional cells in the innermost tissue layer of the bladder. This is the most common cell type.
2. Squamous cell carcinoma. Cancer that develops from squamous cells, which are thin, flat cells that may form in the bladder after long-term infection or irritation.
3. Adenocarcinoma. Cancer that arises from glandular (secretory) cells that may form in the bladder after long-term irritation and inflammation.

• Transitional cell or urothelial carcinoma.

Cancer that derives from transitional cells in the innermost tissue layer of the bladder. This is the most common cell type.

• Squamous cell carcinoma.

Cancer that develops from squamous cells, which are thin, flat cells that may form in the bladder after long-term infection or irritation.

• Adenocarcinoma.

Cancer that arises from glandular (secretory) cells that may form in the bladder after long-term irritation and inflammation.

Ref: N18