Understanding Prostate Cancer
Cancer begins in cells, the building blocks that make up tissues. Tissues make up the organs of the body.
Normally, cells grow and divide to form new cells as the body needs them. When cells grow old, they die, and new cells take their place.
Sometimes this orderly process goes wrong. New cells form when the body does not need them, and old cells do not die when they should. These extra cells can form a mass of tissue called a growth or tumour.
Tumours can be benign( non cancerous) or malignant ( cancerous)
Prostate cancer occurs when the cells in the prostate gland grow out of control. When cells grow out of control, they initially spread within the prostate and then grow through the capsule that covers the prostate into neighboring organs, or break away and spread through the bloodstream and lymphatic system to other parts of the body. Prostate cancer can be relatively harmless or extremely aggressive. Some prostate cancers are slow growing, causing few clinical symptoms. In these cases, a patient will often die with prostate cancer rather than from prostate cancer. Aggressive cancers spread rapidly to the lymph nodes, other organs and especially, bone.
Risk factors for prostate cancer
The chance of an individual developing cancer depends on both genetic and non-genetic factors. A genetic factor is an inherited, unchangeable trait, while a non-genetic factor is a variable in a person's environment, which can often be changed.
Non-genetic factors may include diet, exercise, or exposure to other substances present in our surroundings. These non-genetic factors are often referred to as environmental factors. Some non-genetic factors play a role in facilitating the process of healthy cells turning cancerous (i.e. the correlation between smoking and lung cancer).
Other cancers have no known environmental correlation but are known to have a genetic predisposition. A genetic predisposition means that a person may be at higher risk for a certain cancer if a family member has that type of cancer.
Hereditary or genetic factors
Researchers have estimated that approximately 9% of prostate cancers may be the result of heritable susceptibility genes. Approximately 15% of men with prostate cancer have a first-degree male relative (father or brother) with prostate cancer, compared with 8% of the general population.
Researchers have found that there are 4 alterations or mutations of the Hereditary Prostate Cancer 2 (HPC2) gene. These place men at an increased risk of developing prostate cancer. Two of these alterations result in a 5 to 10 times higher risk of prostate cancer, while the other two result in1.5 to 3 times higher risk of prostate cancer.
Researchers are unsure why one man will develop prostate cancer and another will not. Interestingly, when people from areas with low prostate cancer rates move to areas with higher prostate cancer rates, they assume the rates of their new environment, although their genetic make-up clearly has not changed. This suggests that environmental factors may play a larger role than genetic factors in the development of prostate cancer.
Age: The incidence of prostate cancer increases dramatically with increasing age. It is unusual for prostate cancer to occur in men under the age of 50. Prostate cancer is most common in men over the age of 55, with the average age at diagnosis being 70. The risk of prostate cancer increases exponentially after age 50. In fact, by the age of 60, as many 34% of men show early evidence of prostate cancer, whereas 70% of men in their 80s have the disease.
Diet: There is increasing evidence that diet plays a role in the development of prostate cancer. Some studies indicate that prostate cancer is more prevalent in populations that consume a diet high in animal fat and/or lacking certain nutrients. Many studies indicate that a higher dietary fat intake is related to a higher risk for prostate cancer. In Asian countries where more fish, vegetables, and soy products are eaten, the incidence and death rate from prostate cancer is less than in Western countries.
Lycopenes (antioxidants in tomatoes, pink grape fruit, watermelon); vitamin E (green leafy vegetables and whole grains); selenium (seafood and whole grain) may lower cancer risk.
Hormones: Some research indicates that high testosterone levels may increase the risk of prostate cancer.
Race: Prostate cancer rates are highest among blacks, intermediate among whites and lowest among native Japanese and Native Americans. Black men are nearly twice as likely to develop prostate cancer as white men and are twice as likely to die from the disease.
Factors not likely to present risk: there have been many attempts to link the following with prostate cancer, but there has been little evidence to support this.
- Vasectomy
- smoking
- sexual activity viruses
- Sexually transmitted disease.
Comments