Endometrial cancer begins in the layer of cells that form the lining (endometrium) of the uterus. Endometrial cancer is sometimes called uterine cancer. Other types of cancer can form in the uterus, including uterine sarcoma, but they are much less common than endometrial cancer.
Endometrial cancer is often detected at an early stage because it frequently produces abnormal vaginal bleeding.
Symptoms
Signs and symptoms of endometrial cancer may include:
- Vaginal bleeding after menopause
- Bleeding between periods
- Pelvic pain
Risk factor
Factors that increase the risk of endometrial cancer include:
Causes
- Changes in the balance of female hormones in the body- The ovaries make two main female hormones — estrogen and progesterone. Fluctuations in the balance of these hormones cause changes in the endometrium.
A disease or condition that increases the amount of estrogen, but not the level of progesterone, in your body can increase your risk of endometrial cancer. Examples include irregular ovulation patterns, which might happen in polycystic ovary syndrome, obesity and diabetes. Taking hormones after menopause that contain estrogen but not progesterone increases the risk of endometrial cancer.
A rare type of ovarian tumour that secretes oestrogen also can increase the risk of endometrial cancer. - More years of menstruation. Starting menstruation at an early age before 12 yrs or beginning menopause later increases the risk of endometrial cancer.
- Never having been pregnant. If you've never been pregnant, you have a higher risk of endometrial cancer than someone who has had at least one pregnancy.
- Older age. As you get older, your risk of endometrial cancer increases. Endometrial cancer occurs most often after menopause.
- Obesity. Being obese increases your risk of endometrial cancer. This may occur because excess body fat alters your body's balance of hormones.
- Hormone therapy for breast cancer. Taking the hormone therapy drug tamoxifen for breast cancer can increase the risk of developing endometrial cancer. If you're taking tamoxifen, discuss this risk with your doctor. For most, the benefits of tamoxifen outweigh the small risk of endometrial cancer.
- An inherited colon cancer syndrome. Lynch syndrome, also called hereditary nonpolyposis colorectal cancer (HNPCC), is a syndrome that increases the risk of colon cancer and other cancers, including endometrial cancer. Lynch syndrome is caused by a gene mutation passed from parents to children. If a family member has been diagnosed with Lynch syndrome, discuss your risk of the genetic syndrome with your doctor. If you've been diagnosed with Lynch syndrome, ask your doctor what cancer screening tests you should undergo.
Prevention
To reduce your risk of endometrial cancer, you may wish to:
- Talk to your doctor about the risks of hormone therapy after menopause. If you're considering hormone replacement therapy to help control menopause symptoms, talk to your doctor about the risks and benefits. Unless you've undergone a hysterectomy, replacing estrogen alone after menopause may increase your risk of endometrial cancer. Taking a combination of estrogen and progestin can reduce this risk. Hormone therapy carries other risks, so weigh the benefits and risks with your doctor.
- Consider taking birth control pills. Using oral contraceptives for at least one year may reduce endometrial cancer risk. The risk reduction is thought to last for several years after you stop taking oral contraceptives. Oral contraceptives have side effects, though, so discuss the benefits and risks with your doctor.
- Maintain a healthy weight. Obesity increases the risk of endometrial cancer, so work to achieve and maintain a healthy weight. If you need to lose weight, increase your physical activity and reduce the number of calories you eat each day.