Cancer Prostate

Definition :
Prostate cancer involves a malignant tumor growth within the prostate gland .

The cause of prostate cancer is unknown, although some studies have shown a relationship between high dietary fat intake and increased testosterone levels. When testosterone levels are lowered either by surgical removal of the testicles (castration, orchiectomy) or by medication, prostate cancer can regress. There is no known association with benign prostatic hyperplasia ( BPH ).

Prostate cancer is the third most common cause of death from cancer in men of all ages and is the most common cause of death from cancer in men over 75 years old. Prostate cancer is rarely found in men younger than 40.

Men at higher risk include black men older than 60, farmers, tire workers, painters, and men exposed to cadmium. The lowest incidence occurs in Japanese men and vegetarians.

Prostate cancers are classified or staged based on their aggressiveness and how different they are from the surrounding prostate tissue. There are several different ways to stage tumors; one of the more common is the A-B-C-D staging system (also known as the Whitmore-Jewett system).

• A: tumor not palpable (unable to be felt on physical examination). Usually detected by accident after prostate surgery done for other reasons.
• B: tumor is confined to the prostate and usually detected by physical examination or PSA testing.
• C: extension of tumor beyond the prostate capsule without spread to lymph nodes.
• D: cancer has spread (metastasized) to regional lymph nodes or other parts of the body (bone and lungs for example).

This system also contains several substages.

What Is Prostate Cancer?
The prostate ( pros -tate) is a gland found only in men. The prostate is about the size of a walnut. It is just below the bladder and in front of the rectum. The tube that carries urine (the urethra) runs through the prostate. The prostate contains cells that make some of the seminal fluid. This fluid protects and nourishes the sperm.

Male hormones cause the prostate gland to develop in the fetus. The prostate keeps on growing as a boy grows to manhood. If male hormone levels go down, the prostate gland will not grow to full size or it will shrink. In older men, though, the part of the prostate around the urethra often keeps on growing. This causes BPH (benign prostatic hyperplasia) which can result in problems with urinating.Although there are several cells types in the prostate, nearly all prostate cancers start in the gland cells. This kind of cancer is known as adenocarcinoma. The rest of this information refers only to prostate adenocarcinoma.

Most of the time, prostate cancer grows slowly. Autopsy studies show that many older men who died of other diseases also had prostate cancer that neither they nor their doctor were aware of. But sometimes prostate cancer can grow and spread quickly. Even with the latest methods, it is hard to tell which prostate cancers will grow slowly and which will grow quickly.

Some doctors believe that prostate cancer begins with very small changes in the size and shape of the prostate gland cells. These changes are known as PIN (prostatic intraepithelial neoplasia). These changes can be either low-grade (almost normal) or high-grade (abnormal).

If you have had a prostate biopsy that showed high-grade PIN, there is a greater chance that there are cancer cells in your prostate. For this reason, you will be watched carefully and may need another biopsy.