Hereditary nonpolyposis colon cancer syndrome
Hereditary nonpolyposis colon cancer (HNPCC) syndrome (also known as Lynch Syndrome) is an inheriteddisorder caused by changes in certain genes. Women who have HNPCC syndrome have a much higher risk of developing endometrial cancer than women who do not have HNPCC syndrome.
Other inherited conditions
Polycystic ovary syndrome (a disorder of the hormones made by the ovaries), and Cowden syndrome are inherited conditions that are linked to an increased risk of endometrial cancer.
Obesity increases the risk of endometrial cancer. This may be because obesity is related to other risk factors such as estrogen levels, polycystic ovary syndrome, lack of physical activity, and a diet that is high in saturated fats.
It is not known if losing weight decreases the risk of endometrial cancer.
The following protective factors may decrease the risk of endometrial cancer:
Combination oral contraceptives
Taking contraceptives that combine estrogen and progestin (combination oral contraceptives) decreases the risk of endometrial cancer. The protective effect of combination oral contraceptives increases with the length of time they are used, and can last for many years after oral contraceptive use has been stopped.
While taking oral contraceptives, women have a higher risk of blood clots, stroke, and heart attack, especially women who smoke and are older than 35 years.
Physical activity may lower the risk of endometrial cancer.
Pregnancy and breast-feeding
Estrogen levels are lower during pregnancy and when breast-feeding. Being pregnant and/or breast-feeding may lower the risk of endometrial cancer. The risk of endometrial cancer may be lower in women who have a higher number of pregnancies and who breast-feed for more than 18 months.
A diet low in saturated fats and high in fruits and vegetables may lower the risk of endometrial cancer. The risk may also be lowered when soy-based foods are a regular part of the diet.
Cancer prevention clinical trials are used to study ways to prevent cancer.
Cancer preventionclinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.
The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include eating fruits and vegetables, exercising, quitting smoking, or taking certain medicines, vitamins, minerals, or food supplements.
New ways to prevent endometrial cancer are being studied in clinical trials.
Clinical trials are taking place in many parts of the country. Information about clinical trials can be found in the Clinical Trials section of the NCI Web site. Check NCI's PDQ Cancer Clinical Trials Registry for endometrial cancer prevention trials that are now accepting patients.