Modifiable Factors for Prevention of Prostate Cancer …… 3
Dr. Ulhas Ganu / April 19, 2016 /
A risk factor is anything that affects ones chance of getting a disease, be it diabetes, cardiac problems or cancer. Different cancers have different risk factors. Risk factors are of two kinds: Genetic, related to family history which cannot be changed and Lifestyle related, like eating habits or smoking, which can be changed.
Yet we also observe that many people with one or even multiple risk factors may not get cancer, while others who get cancer may have had few or no known risk factors. Although the exact causes of Prostate Cancer have not been understood as yet, researchers have found several factors that might affect a man’s risk of getting it.
Prostate Cancer is essentially the disease of the old. Very rarely found in men younger than 40, the chance of having Prostate Cancer rises rapidly after age 50. In the US, about 6 in 10 cases of Prostate Cancer are found in men over the age of 65.
Prostate Cancer occurs more often in African-American men and in Caribbean men of African ancestry than in men of other races. African-American men are also more than twice as likely to die of prostate cancer as white men. Asian-American and Hispanic/Latino men are less likely to get Prostate cancer than non-Hispanic whites, the reasons for such racial and ethnic differences as well as for geographic differentiation are not clear.
Lifestyle differences such as diet are likely to be important as well. Men of Asian descent living in the United States continue to have a lower risk of Prostate Cancer than white Americans, but their risk is higher than that of men of similar backgrounds living in Asia. Prostate cancer seems to run in some families, which is suggestive of an inherited or genetic factor. Having a father or brother with prostate cancer more than doubles a man’s risk of developing this disease. The risk is higher for men who have a brother with the disease than for those with an affected father.
Although several inherited gene changes have been shown to be associated with increased Prostate Cancer risk, they account for only a small percentage of cases overall. For example mutation in BRCA1 or BRCA2 genes (associated with increased risk of breast and ovarian cancers in women in some families) may also increase Prostate Cancer risk in some men.
Men with Lynch syndrome (also known as hereditary non-polyposis colorectal cancer), a condition caused by inherited gene changes, have an increased risk for a number of cancers, including Prostate Cancer. Other inherited gene changes can also raise a man’s risk of prostate cancer. Recently, some common gene variations have been linked to a higher risk of prostate cancer. Studies to confirm this are needed to see if testing for the gene variants will be useful in predicting prostate cancer risk.
The exact role diet in Prostate Cancer has not been established. Several factors such as eating a lot of red meat or high-fat dairy products along with lower consumption of fruits and vegetables appears to increase chances of getting prostate cancer, albeit slightly. Thus experts advise avoiding beef, pork and lamb and shifting to fish and poultry. Consuming fruits and vegetables regularly also makes lot of sense.
There are conflicting reports about calcium intake with no concrete evidence to implicate calcium. Calcium, no doubt, is important for bone health and of immense value in preventing osteoporosis for the elderly. Some studies have suggested that men who consume a lot of calcium (through food or supplements) may have a higher risk of developing Prostate Cancer. Most studies have not found such a link with the levels of calcium found in the average diet. Your doctor is the best judge on daily quantity of supplementary calcium as it is important to note that calcium is known to have many important health benefits.
Obesity & Smoking
Some studies have found that obese men may be at greater risk for having more advanced prostate cancer and of dying from prostate cancer. However, most of the studies do not report such a correlation. There is no conclusive proof of obesity being a cause of Prostate Cancer.
Although a small possible risk between smoking and Prostate Cancer is proposed by some research workers, as such no direct link has been established between smoking and enhanced risk for Prostate Cancer. Anyway it helps to keep better health by quitting smoking.
There is some evidence that firefighters are exposed to substances (toxic combustion products) that may increase their risk of prostate cancer.
Inflammation of the prostate
According to some researchers Prostatitis (inflammation of the prostate gland) may be linked to an increased risk of Prostate Cancer. Though inflammation is often seen in samples of prostate tissue that also contains cancer, direct link between inflammation and Prostate Cancer appears to be weak as many other researchers could not corroborate the theory.
The evidence to correlate Vasectomy and Sexually transmitted infections to Prostate Cancer is also very weak and nothing conclusive can be stated in the matter.
Although we do not know exactly as to what causes prostate cancer, we do know that on a basic level, Prostate Cancer is caused by changes in the DNA of a prostate cell. Growth, division and death of our body cells (apoptosis – programmed cell death) are decided by the genes. Oncogenes are the Genes that help cells grow, divide, and stay alive. On the contrary there are (Tumor) Suppressor Genes which (normally) slow down cell division, repair mistakes in DNA, or cause cells to die at the right time.
DNA changes can either be inherited from a parent or can be acquired during a person’s lifetime. DNA changes (mutations) may turn on Oncogenes or turn off Tumor Suppressor Genes, which may lead to cancer. Inherited DNA changes in certain genes seem to cause only about 5% to 10% of prostate cancers. Several mutated genes have been linked to a man’s inherited tendency to develop prostate cancer, including RNASEL (formerly HPC1). The normal function of this tumor suppressor gene is to help cells die when something goes wrong inside them. Inherited mutations in this gene might let abnormal cells live longer than they should, which can lead to an increased risk of prostate cancer.
Tumor suppressor genes BRCA1 and BRCA2 normally help repair mistakes in a cell’s DNA or cause the cell death in case the mistake is irreparable. Inherited mutations BRCA1 and BRCA2 commonly cause breast and ovarian cancer in women. In a very small number of men, inherited BRCA changes may account for Prostate Cancers. DNA mismatch repair genes such as MSH2 and MLH1 normally help rectify mismatches in DNA during cell division. Men with inherited mutations in these genes have a condition known as Lynch syndrome, which puts them at increased risk of Colorectal and Prostate Cancers.
Most DNA mutations related to prostate cancer seem to develop during a man’s life rather than having been inherited.
Can prostate cancer be prevented?
Since diverse risk factors are involved from genetic to age, race and demography which cannot be controlled the exact cause of Prostate Cancer cannot be pinpointed. Naturally it is not possible to lay down an algorithmic path for prevention either.
Body weight, physical activity, and diet
The effects of body weight, physical activity, and diet on prostate cancer risk are not clear, but there are things one can do that might lower ones risk, such as: Eating at least 2½ cups of a wide variety of vegetables and fruits each day, being physically active and maintaining a healthy weight.
- American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention.
American Cancer Society: http://www.cancer.org/acs/groups/cid/documents/webcontent/003134-pdf.pdf