Obesity Increases The Risk Factor
Causes Of Endometrial Cancer
• What Causes Endometrial Cancer?
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|What Causes Endometrial Cancer?
Scientists are still not sure what causes endometrial cancer (also known as uterine or womb cancer). That said they have linked a number of risk factors to the disease. Although a risk factor does not cause a disease, it can raise the person's risk of developing it. For example smoking is a risk factor for lung cancer and exposure to direct sunlight is a risk factor for skin cancer. Some risk factors we can do something about - such as obesity and alcohol consumption, while others we cannot - such as ethnicity, age and gender. This is explained in our article on cancer causes. Yet risk factors are not conclusive - just because you have a risk factor for endometrial cancer does not mean you will develop the disease. Even then, if you do develop cancer there is no way of knowing which risk factor was the main influence. In fact, there may even be a chance that you have none of the risk factors at all.
List of Known Risk Factors
Nearly half of all uterine cancers occur in postmenopause women between the ages of 50 and 69. However, although the risk of cancer increases with age, 20 percent of cases are still discovered in premenopausal women and 5 percent in women under the age of 40. For this reason, doctors who suspect a woman may be showing symptoms of endometrial cancer should not rule out the disease based on the woman's age alone.
Women who have had prolonged and excessive exposure to the hormone estrogen, relative to progesterone, are at increased risk of endometrial cancer. During a woman's reproductive years her ovaries produces both estrogen and progesterone and the balance of these hormones shifts during a menstrual cycle. The more periods a woman has over a lifetime the higher her risk of cancer - that means women who start their periods (menarche) younger than the average age (12), women who do not have children (pregnant women do not have periods) and those who experience menopause later in life. Menopause brings its own set of problems. When a woman enters menopause, her ovaries stop producing estrogen and progesterone but small amounts of estrogen are still excreted from fat cells in the body. This increases the risk factor significantly because the womb in no longer protected by progesterone.
On the other hand, missing periods (amenorrhea) or irregular periods (oligomenorrhea) raises the risk of womb cancer in younger women. Most endometrial cancers which occur in younger women typically present in those who also have excessive androgen male hormones. Androgens cause excessive facial hair, a deepening of the voice and abnormal amounts of muscle mass. This is because failure to ovulate, common to all these conditions, can result in the endometrium being over stimulated with estrogen without the balancing effect of progesterone (which is only usually produced when ovulation has occurred).
Studies show that women who took estrogen replacement therapy (ERT) without progesterone to help treat symptoms of menopause are at higher risk. This is known as 'unopposed' use of estrogen and the risk of cancer increases with the dose of estrogen and length of period it was taken. For this reason, since the 1980s doctors now prescribe hormone replacement therapy (HRT) which includes both forms of hormones, or they prescribe a progesterone supplement with ERT. The progesterone 'opposes' the estrogen and works by protecting the womb.
Women with a family history of Lynch syndrome have a higher chance of developing both endometrial and colon cancer. Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), is a type of cancer which affects the digestive tract, in particular the colon and rectum. Up to 65 percent of women who contract this inherited disorder develop endometrial cancer. Genetic testing can highlight a person's risk of the syndrome. While there is no cure, those at risk can be better monitored for warning signs of endometrial cancer as well as other cancers. If you have a family history of Lynch syndrome, it is important to talk to a genetic counselor.
Women who have had breast or ovarian cancer are more likely to develop endometrial cancer than those who have not. Furthermore, women who have taken the drug tamoxifen as treatment for or to prevent breast cancer have a slightly higher risk again (See breast cancer risk factors). About 1 in 500 women who take tamoxifen develop womb cancer. Other cancer treatments such as radiation therapy to the pelvic area for other diseases may increase the risk of a second cancer such as endometrial cancer. Anywhere between 10 and 25 percent of women with uterine cancer may have received pelvic radiation between 5 and 25 years before the disease developed.
Certain conditions which affect the ovaries may increase the risk of cancer - such as granulosa-theca cell tumors which are usually benign tumors of the ovaries. Women with PCOS syndrome, a condition that is characterized by multiple ovarian cysts together with other symptoms, are also at increased risk. This is because PCOS results in abnormal levels of estrogen production.
|Related Articles on Uterine Cancers
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