mardi 10 mai 2016

CAUSES OF PROSTATE CANCER


The PSA blood test is used to screen for prostate cancer and to monitor treatment of the disease.  PSA, which stands for prostate specific antigen, is a fluid produced by the prostate gland and normally present in semen.  Elevated levels of PSA in the blood are associated with benign prostatic hyperplasia (prostate enlargement) and prostate cancer.Prostate Gland
 

The prostate is a small gland the size of a walnut in the male reproductive system.  It is located in front of the rectum and just below the bladder.  The prostate gland makes and stores a fluid that is released with the ejaculate (seminal fluid) to protect and nourish the sperm.

Out of every 100 men who are 60 years old today, 6 or 7 will get prostate cancer by the age of 70.Centers for Disease Control


Experts do not completely understand the causes of prostate cancer, but there are several factors which seem to influence the risk of getting prostate cancer. The incidence of prostate cancer seems to be higher with age, a family history of prostate cancer, and a high-fat diet. Research has also shown that race or ethnicity, hormones, and lifestyle choices may be risk factors of prostate cancer.


Men should be aware that risk factors do not always pre-determine who will and will not get prostate cancer.  In some cases, men who are not in a high risk category may still develop prostate cancer and men who are at a higher risk will not develop the disease.  However, knowing the risk factors may be helpful to men who are trying to decide whether to undergo prostate cancer screening.Contributing Factors of Prostate CancerGender - Only men get prostate cancer, as it is cancer that begins in the prostate, a gland in the male reproductive system.Age - Age increases the chance of getting prostate cancer.  After the age of 50, the chance of getting prostate cancer increases substantially.  More than 70 percent of the men diagnosed with prostate cancer are at least 65 years old.Race or ethnicity - The reasons are not clear, but some racial and ethnic groups are more likely to develop prostate cancer than others.  Statistics show that prostate cancer is more common in African-American men than white or Hispanic/Latino men and less common among Asian/Pacific Islander and American Indian/Alaska Native men.Heredity - While most of the men who are diagnosed with prostate cancer have no family history of the disease, a man's chance of getting prostate cancer is higher than the average man if he has a close relative (such as a father or brother) who was diagnosed with prostate cancer.  The chances increase more if the family member was younger than 55 years of age when the cancer was found or if several family members are affected. Diet - The chance of getting prostate cancer seems to be linked to a high-fat diet. <a href="http://prostatecanceruk. <a href="http://www. <a href="http://www. <a href="https://www.breastcancercare.org.uk/">breast cancer</a> cancerresearchuk.org/about-cancer/type/ovarian-cancer/"> Ovarian cancer UK Reseach</a> dermatology.ca/fr/peau-cheveux-ongles/la-peau/cancer-de-la-peau/">  Cancer de la peau</a> org">  prostate cancer UK</a>  Studies have shown that a man is more likely to develop prostate cancer and not survive it if he lives in a country where high-fat diets are common than a man who lives in a country where low-fat diets are common.  Men who eat a lot of red meat or high-fat dairy products appear to have a higher incidence of prostate cancer.Exercise & Weight - Studies are mixed, but engaging in regular physical activity and maintaining a healthy weight may lower the risk of prostate cancer.High testosterone levels - Men with high levels of testosterone (such as those with hypogonadism or those who use testosterone therapy) have a greater chance of getting prostate cancer than men with lower levels of the hormone.  This is due to the nature of testosterone to stimulate growth of the prostate gland.  Testosterone used for hormone treatments may also speed up the growth of prostate cancer that is already present.Prevention of Prostate Cancer

Most cases of prostate cancer cannot be prevented as the exact cause is not known and many of the known risk factors, such as gender, age, race or ethnicity, or heredity, cannot be controlled.  Some lifestyle factors can be controlled, however, and might be important for prevention.Lifestyle Choices


Some of the known risk factors, such as lifestyle choices of diet and physical activity, can be controlled and may have an impact on preventing or delaying the onset of the disease.

Eat a healthy, low-fat, high-fiber diet

Eat a diet high in fruits and vegetables

Maintain a healthy weight

Engage in regular exercise/physical activity

Limit saturated fats, red meat, and high-fat dairy products


Research is ongoing into the affect of dietary choices but some of the foods that may help prevent or delay prostate cancer are soy products (tofu and soy beans), tomatoes, fish that have omega-3 fatty acids, foods that contain tomato sauce, broccoli, cauliflower, and cabbage.  Dietary supplements may also provide a benefit - studies are being done to test the benefits of vitamins D and E, selenium, and green tea in helping to prevent prostate cancer.Medications


New information suggests that certain medications, finasteride and dutasteride, may help reduce the risk of prostate cancer, but there are also side effects and costs.


The medications, which are classified as 5 alpha-reductase inhibitors, block the enzyme 5 alpha-reductase that changes testosterone into dihydrotestosterone (DHT).  DHT is the hormone which causes the prostate to grow.  By blocking the enzyme, these medications prevent the formation of DHT.


Study results are still preliminary and not all doctors agree that taking a 5 alpha-reductase inhibitor to prevent prostate cancer is a good thing.  Further studies are ongoing to find out more about the benefits and risks of finasteride and dutasteride in preventing prostate cancer.