FACTBOX-What is prostate cancer?

Oct 29 (Reuters) - Israeli Prime Minister Ehud Olmert said on Monday that a cancerous growth was found in his prostate gland but that it would not affect his ability to remain in office. Olmert said he will undergo minor surgery to remove what he described as a "microscopic growth" that is not life-threatening.

Here are some details about prostate cancer:

* WHAT IS THE PROSTATE?

-- The prostate is a walnut-sized gland that only men have. It is part of the reproductive system that makes the fluid that carries sperm. The urethra -- the tube that carries urine from the bladder to outside the body -- runs through the centre of the prostate. As men age, the prostate tends to increase in size. This can cause the urethra to narrow and decrease urine flow.

* WHAT IS PROSTATE CANCER?

-- Prostate cancer is made up of cells that do not grow normally. The cells divide and create new cells that the body does not need, forming a mass of tissue called a tumour. These abnormal cells sometimes spread to other parts of the body, multiply, and cause death.

* WHAT CAUSES PROSTATE CANCER?

-- As with many types of cancers, medical experts do not know what causes prostate cancer.

* IS PROSTATE CANCER SERIOUS?

-- Some prostate cancers become a serious threat to health by growing quickly, spreading beyond the prostate gland to other parts of the body, and causing death. Yet other prostate cancers grow slowly and never become a serious threat to health or affect how long a man lives. (Source: Reuters/Centers for Disease Control and Prevention www.cdc.gov)