Uterine Cancer

Uterine, or endometrial, cancer is one of the most common cancers in women. In fact, about 37,000 American women receive a diagnosis of endometrial cancer each year, making it the fourth most common cancer found in women — after breast cancer, lung cancer and colon cancer.

Endometrial cancer begins in the lining of the uterus (endometrium). The uterus is a hollow, pear-shaped organ where a baby develops during pregnancy. Endometrial cancer most often occurs after the reproductive years, in women between the ages of 50 and 70.

Endometrial cancer is often detected at an early stage because it frequently produces vaginal bleeding between periods or after menopause. If discovered early, this slow- growing form of cancer is likely to be confined to the uterus. Removing the uterus surgically often eliminates the cancer. In fact, early-stage endometrial cancer is successfully treated more than 80 percent of the time. However, the death rate from endometrial cancer has increased over the past 10 years. Researchers aren't sure why.

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Endometrial cancer often develops over a period of years. Your first clue that something is wrong may be vaginal bleeding that's uncommon for you.
Most cases of endometrial cancer develop in postmenopausal women whose periods have stopped. However, about 20 percent of cases affect younger women. Signs and symptoms may include:

• Heavy periods or bleeding between periods
• Vaginal bleeding or spotting during perimenopause (the time just before menopause) or after menopause
• A pink, watery or white discharge from your vagina
• Pelvic pain, especially late in the disease
• Pain during intercourse
• Weight loss

Some endometrial cancers may reach an advanced stage before signs and symptoms are present. But this is rare.

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The female reproductive system consists of two ovaries, two fallopian tubes and a uterus. The ovaries produce two main female hormones — estrogen and progesterone. The balance between these two hormones changes each month, helping the endometrium thicken in case pregnancy occurs or shed tissue if it doesn't.

When the balance of these two hormones shifts toward more estrogen — which stimulates growth of the endometrium — a woman's risk of developing endometrial cancer increases. Factors that increase levels of estrogen in the body include:

• Many years of menstruation - If you started menstruating at an early age — before age 12 — and continue to have monthly periods into your 50s, you're at greater risk of endometrial cancer than a woman who menstruated for fewer years. The more years you have a monthly period, the more exposure your endometrium has had to estrogen.
• Never having been pregnant - The body produces more progesterone during a pregnancy, helping protect you from endometrial cancer by lowering levels of estrogen. If you've never been pregnant, you don't get the benefit of this protection.
• Irregular ovulation - Ovulation, the monthly release of an egg from an ovary in menstruating women, is regulated by estrogen. Irregular ovulation or failure to ovulate can increase your lifetime exposure to estrogen. Ovulation irregularities have many causes, including obesity and a condition known as polycystic ovary syndrome (PCOS). This is a condition in which hormonal imbalances prevent ovulation and menstruation. Treating obesity and PCOS can help restore your monthly ovulation and menstruation cycle, decreasing your risk of endometrial cancer.
• Obesity - Ovaries aren't the only source of estrogen. Fat tissue can change some hormones into estrogen. Being obese — defined roughly as being 30 pounds or more overweight — can increase levels of estrogen in your body, putting you at risk of endometrial cancer and other cancers. A high-fat diet also can add to your risk by promoting obesity. Some scientists even think that fatty foods may directly affect estrogen metabolism, further increasing a woman's risk of endometrial cancer.
• Diabetes This is a risk factor for endometrial cancer mainly because obesity and type 2 diabetes (formerly called adult-onset or noninsulin-dependent diabetes) often go hand in hand. However, some data suggest that women who have diabetes, whether they're obese or not, are at greater risk of endometrial cancer.
• Estrogen replacement therapy (ERT) - Estrogen stimulates growth of the endometrium. Replacing estrogen alone after menopause may increase your risk of endometrial cancer. However, taking synthetic progestin, a form of the hormone progesterone, with estrogen — combination hormone replacement therapy — causes the lining of the uterus to shed and actually lowers your risk.
• Ovarian tumors - Some tumors of the ovaries may themselves be a source of estrogen, increasing estrogen levels.

Other factors that can increase your risk of endometrial cancer include:

• Age - Most endometrial cancers develop over many years. Therefore, the older you are, the greater your risk. Endometrial cancer most often occurs in women between the ages of 50 and 70.
• Family history of endometrial cancer - Endometrial cancer can run in some families, especially those who have an inherited risk of certain types of colon cancer. If colon cancer and endometrial cancer run in your family, you may have an inherited risk of these cancers.
• Personal history of breast cancer or ovarian cancer - Some of the same risk factors for breast cancer and ovarian cancer also increase your risk of endometrial cancer.
• Prior pelvic radiation treatment - Radiation of the pelvic region to treat ovarian cancer or another cancer can damage cells, sometimes increasing the risk of developing a second cancer such as endometrial cancer.
• Tamoxifen treatment - Endometrial cancer has been found in two out of every 1,000 breast cancer patients who have been treated with the hormonal drug tamoxifen. The drug acts like an estrogen, causing the uterine lining to grow. If you're being treated with this hormone, see your doctor for an annual pelvic examination and be sure to report any unusual vaginal bleeding.
• Hereditary nonpolyposis colorectal cancer (HNPCC) - This inherited disease is rare and results in colon cancer at a young age. The cause is an abnormality in a gene important for DNA repair. Women with HNPCC are at high risk of uterine cancer.

Having risk factors for endometrial cancer doesn't mean you'll get the disease. It means that you're at risk and should be alert to possible signs and symptoms of the disease. Conversely, some women who develop endometrial cancer — and often a more aggressive form — appear to have no risk factors for the disease.

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When discovered early, endometrial cancer is usually confined to a small area of the uterus, making it highly treatable. However, in some women endometrial cancer reaches an advanced stage before diagnosis.
Endometrial cancer can cause pelvic pain and painful urination. As the cancer advances, symptoms may worsen. Treating the cancer can help alleviate the pain, but recovery can be slow.

Women with endometrial cancer tend also to lose blood from vaginal bleeding. Over time, chronic loss of blood can result in anemia — a condition in which the blood is low on red blood cells and oxygen. Anemia causes fatigue and shortness of breath. But anemia can be treated along with your cancer, helping you regain energy.

Finally, endometrial cancer can recur in some women who don't have their uterus removed during treatment.

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Although most cases of endometrial cancer aren't preventable, certain factors can lower your risk of developing the disease. These include:

• Being on hormone replacement therapy (HRT) using progestin - Estrogen stimulates growth of the endometrium. Replacing estrogen alone after menopause may increase your risk of endometrial cancer. Taking synthetic progestin, a form of the hormone progesterone, with estrogen causes the lining of the uterus to shed. This kind of combination HRT lowers your risk. But not all effects of HRT are positive. Taking HRT as a combination therapy can result in serious side effects and health risks. Work with your doctor to evaluate the options and decide what's best for you.
• A history of using birth control pills - Use of oral contraceptives can reduce endometrial cancer risk. The risk is lowest in women who take oral contraceptives for many years, and this protection continues for at least 15 years after a woman stops taking them.

You can also help prevent endometrial cancer by maintaining a healthy weight. Excess fat tissue can change some hormones into estrogen, increasing the levels of estrogen in your body and increasing your risk of endometrial cancer. Maintaining a healthy weight as you age lowers your risk of endometrial cancer as well as other diseases.

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For women at high risk, an endometrial biopsy is recommended at menopause and several points thereafter.

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Treatment usually includes surgery to remove the uterus, or a total hysterectomy (including removal of the ovaries), followed by radiation, hormones, and chemotherapy, if needed.

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93% of uterine cancer patients survive for only one year if the cancer is caught in a late stage. However, if caught early, 95% of patients can expect to live for five years or more. The survival rate drops to 64% if the woman is diagnosed with the cancer at a regional stage.

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* Text Resources: The Mayo Clinic Staff