Endometrial cancer involves cancerous growth of the endometrium (lining of the uterus). This type of uterine cancer originates in the inner lining of the uterus, accounts for about 90% of uterine cancers.
Uterine sarcoma originates in the myometrium and accounts for less than 10% of cases.
Endometrial cancer is the rapid and uncontrolled growth of cells in the endometrium, the lining of the uterus. The uterus is the hollow, pear-shaped organ in a woman’s abdomen. Endometrial cancer usually occurs in women older than 50.
Fortunately, it is highly curable if detected at an early stage when the cancer is still contained in the uterus. Most women with endometrial cancer are diagnosed in the earliest stage, and up to 93% of these women are cancer-free 5 years after treatment.
Endometrial cancer the cancer of the womb (the uterus) occurs most often in women between the ages of 55 and 70 years. It accounts for about 6% of cancer in women.
Women at elevated risk for endometrial cancer include those who are obese, who have few or no children, who began menstruating at a young age, who had a late menopause, and women of high socioeconomic status. It is thought that most of these risk factors are related to hormones, especially excess estrogen.
Cause of Endometrial Cancer
Endometrial cancer is the most common type of uterine cancer. Although the exact cause of endometrial cancer is unknown, increased levels of estrogen appear to have a role. One of estrogen’s normal functions is to stimulate the buildup of the epithelial lining of the uterus. Excess estrogen administered to laboratory animals produces endometrial hyperplasia and cancer.
The incidence peaks between the ages of 60 and 70 years, but 2% to 5% of cases may occur before the age of 40 years. Increased risk of developing endometrial cancer has been noted in women with increased levels of natural estrogen.
The exact cause of endometrial cancer is unknown. Associated conditions include the following:
- Polycystic ovarian disease
- Increased risk is also associated with the following:
- Nulliparity (never having carried a pregnancy)
- Infertility (inability to become pregnant)
- Early menarche (onset of menstruation)
- Late menopause (cessation of menstruation)
- Women who have a history of endometrial polyps or other benign growths of the uterine
- Chronic exposure to estrogen increases the risk for developing the disease and estrogen often affects tumor growth.
- Long-term use of tamoxifen (e.g., Nolvadex®) increases the risk for endometrial cancer.
- Age (more common after age 50)
- Family history of endometrial cancer
- Personal history of breast, colorectal, or ovarian cancer
- Prior pelvic radiation therapy
- Race (endometrial cancer is more common in Caucasian women)
The following factors increase estrogen exposure:
- Early menarche (beginning menstruation before age 12)
- Hormone replacement therapy (HRT) with exogenous estrogen (i.e., without progesterone)
- Late menopause (after age 52)
- Presence of an estrogen-secreting tumor (e.g., some types of breast cancer)
- Nulliparity (having never given birth) or low parity
Endometrial hyperplasia is a condition that increases the risk for uterine cancer, about one-third of patients with hyperplasia develops endometrial cancer.
Tamoxifen is used to treat breast cancer and to decrease the risk for the disease in certain high-risk patients. Women undergoing treatment with tamoxifen are monitored carefully for uterine abnormalities.
Medical conditions such as obesity, gall bladder disease, diabetes mellitus, and high blood pressure (hypertension) increase the risk for endometrial cancer.
Endometrial Cancer Symptoms or Sign of Endometrial Cancer
Early endometrial cancer usually is asymptomatic this means that no endometrial cancer symptoms are evident in the early stage of the disease. Some of the endometrial cancer symptoms include:
- Heavy or prolonged menstrual periods, bleeding between menstrual periods
- Prolonged amenorrhea (i.e., absence of menstruation for longer than 90 days).
- Postmenopausal women with hyperplasia may experience vaginal bleeding or spotting.
- Abnormal uterine bleeding, abnormal menstrual periods
- Bleeding between normal periods in premenopausal women
- Abnormal vaginal bleeding and/or spotting in postmenopausal women
- in women older than 40: extremely long, heavy, or frequent episodes of bleeding (may indicate premalignant changes)
- Lower abdominal pain
- Thin white or clear vaginal discharge in postmenopausal women
- Abnormal vaginal discharge
- Painful or difficult urination
- Pelvic pain or pelvic cramping
- Pain during intercourse
Advanced endometrial cancer may cause weight loss, loss of appetite, and changes in bladder and bowel habits.
Endometrial Cancer Treatment
Endometrial cancer treatment may involve surgery, radiation therapy, hormone therapy or chemotherapy. In its early stage, endometrial cancer is usually treated by surgery. The uterus and cervix are removed by hysterectomy.
Radiation therapy may be done before surgery to shrink the cancer or after surgery to prevent recurrence of the cancer.
A combination of external and internal radiation therapy is often used. If the cancer has spread extensively or has recurred after treatment, a female hormone (progesterone) or chemotherapy may be recommended.
Women with the early stage 1 disease may be candidates for treatment with surgical hysterectomy, but removal of the tubes and ovaries (bilateral salpingo-oophorectomy) is also usually recommended for two reasons.
Tumor cells can spread to the ovaries very early in the disease, and any dormant cancer cells that may be present could possibly be stimulated by estrogen production by the ovaries.
Abdominal hysterectomy is recommended over vaginal hysterectomy because it affords the opportunity to examine and obtain washings of the abdominal cavity to detect any further evidence of cancer.
Women with stage 1 disease who are at increased risk for recurrence and those with stage 2 disease are often offered surgery in combination with radiation therapy. Chemotherapy may be considered in some cases, especially for those with stage 3 and 4 disease.
Endometrial Cancer Prognosis
Because endometrial cancer is usually diagnosed in the early stages (70% to 75% of cases are in stage 1 at diagnosis; 10% to 15% of cases are in stage 2; 10% to 15% of cases are in stage 3 or 4), there is a better probable outcome associated with it than with other types of gynecological cancers such as cervical or ovarian cancer.
The probable endometrial cancer prognosis and the 5-year survival rate following appropriate treatment are:
- 70% to 95% for stage 1
- 50% for stage 2
- 30% for stage 3
- Less than 5% for stage 4
Endometrial Cancer Prevention
For Endometrial cancer prevention all women should have regular pelvic exams and Pap smears (beginning at the onset of sexual activity or at the age of 20 if not sexually active) to help detect signs of any abnormal development.
Since conditions associated with increased risk have been identified, it is important for women with such conditions to be followed more closely by their physicians. Frequent pelvic examinations and screening tests, including a pap smear and endometrial biopsy, should be done.
Women who are taking estrogen replacement therapy should also take these precautions. Any of the following symptoms should be reported immediately to the doctor:
- bleeding or spotting after intercourse or douching
- bleeding that lasts longer than 7 days
- periods that recur every 21 days or less
- Reappearance of blood or staining after six months or more of no bleeding at all.