Prostate Cancer I

What is Prostate Cancer?

Prostate cancer is a malignant tumor that begins in the prostate gland of men. Over 95% of prostate cancers are adenocarcinomas, cancers that develop in glandular tissue. Another important type of prostate cancer is known as neuro-endocrine or small cell anaplastic cancer. This type tends to spread (metastasize) earlier, but does not produce prostate specific antigen (PSA), a tumor marker discussed below.
The prostate is a walnut-sized gland located behind the base of the penis, in front of the rectum and below the bladder. It surrounds the urethra, the tube-like channel that carries urine and semen through the penis. The prostate's main function is to produce seminal fluid, the liquid in semen that protects, supports and helps transport sperm.
Some prostate cancers grow very slowly and might not cause problems for years. Many men with slow-growing prostate cancer may co-exist with their disease and die of something else. But if cancer does spread quickly to other parts of the body, treatment can help manage cancer and control pain, fatigue, and other symptoms.
As we well know, there are many kinds of cancer; unfortunately they all come about because of the out-of-control growth of abnormal cells.

Why is prostate cancer important?

In 2003, 235,000 new cases of prostate cancer were diagnosed in the United States. What's more, 41,000 deaths related to prostate cancer are expected in the year 2004. Thus, prostate cancer is the most common malignancy in American men and the second leading cause of deaths from cancer, after lung cancer. Most experts in this field, therefore, recommend that beginning at age 40, all men should undergo yearly screening for prostate cancer.

What causes prostate cancer?

The cause of prostate cancer is unknown, but the cancer is thought not to be related to benign prostatic hypertrophy (BPH). The risk (predisposing) factors for prostate cancer include advancing age, genetics (heredity), hormonal influences, and such environmental factors as toxins, chemicals, and industrial products. The chances of developing prostate cancer increase with age. Thus, prostate cancer under age 40 is extremely rare, while it is common in men older than 80 years of age. As a matter of fact, some studies have suggested that among men over 80, between 50 and 80 percent of them may have prostate cancer!Genetics (heredity), as just mentioned, plays a role in the risk of developing a prostate cancer. For example, black American men have a higher risk of getting prostate cancer than do Japanese or white American men. Environment, diet, and other unknown factors, however, can modify such genetic predispositions. For example, prostate cancer is uncommon in Japanese men living in their native Japan. However, when these men move to the United States, their incidence of prostate cancer rises significantly. Prostate cancer is also more common among family members of individuals with prostate cancer. Thus, a person whose father, grandfather, or even uncle has prostate cancer is at an increased risk for also developing prostate cancer. To date, however, no specific prostate cancer gene has been identified and verified. (Genes, which are situated on chromosomes within the nucleus of cells, are the chemical compounds that determine specific traits in individuals.)Testosterone, the male hormone, directly stimulates the growth of both normal prostate tissue and prostate cancer cells. Not surprisingly, therefore, this hormone is thought to be involved in the development and growth of prostate cancer. The important implication of the role of this hormone is that decreasing the level of testosterone should be (and usually is) effective in inhibiting the growth of prostate cancer.Environmental factors, such as cigarette smoking and diets that are high in saturated fat, seem to increase the risk of prostate cancer. Additional substances or toxins in the environment or from industrial sources might also promote the development of prostate cancer, but these have not yet been clearly identified