Endometrial cancer involves cancerous growth of the endometrium, the lining of the uterus.
Causes, incidence, and risk factors
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 of endometrial cancer in women in the U.S. is 1 - 2%. The incidence peaks between the ages of 60 and 70 years, but 2 - 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.
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 lining, postmenopausal women who use estrogen-replacement therapy (specifically if not given in conjunction with periodic progestin), and those with diabetes are also at increased risk.
Tamoxifen, a drug used to treat breast cancer, may also increase the risk of developing endometrial cancer.
- Abnormal uterine bleeding, abnormal menstrual periods o Bleeding between normal periods in premenopausal women o Vaginal bleeding 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 or pelvic cramping
- Thin white or clear vaginal discharge in postmenopausal women
Signs and tests
A pelvic examination is frequently normal, especially in the early stages of disease. Changes in the size, shape or consistency of the uterus or its surrounding, supporting structures may exist when the disease is more advanced.
- A Pap smear may be either normal or show abnormal cellular changes.
- Endometrial aspiration or biopsy may assist the diagnosis.
- A dilation and curettage (D and C) procedure may be necessary for diagnosing and evaluating the cancer.
Stages of endometrial cancer:
1. The cancer is confined to the uterine body.
2. The cancer involves the uterine body and the cervix, but does not extend any farther.
3. The cancer extends outside of the uterus but not beyond the true pelvis (gynecological organs). Cancer may involve the lymph nodes in the pelvis or near the aorta (the major artery in the abdomen).
4. The cancer has either spread to the inner surface of the bowel or bladder, or has spread beyond the true pelvis into the abdomen or to distant organs.
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 2 reasons:
- Tumor cells can spread to the ovaries very early in the disease
- 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.
The stress of illness may be eased by joining a support group whose members share common experiences and problems. See cancer - support group.
Because endometrial cancer is usually diagnosed in the early stages (70 - 75% of cases are in stage 1 at diagnosis, 10 - 15% of cases are in stage 2, 10 - 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 5-year survival rate for endometrial cancer following appropriate treatment is:
- 75 - 95% for stage 1
- 50% for stage 2
- 30% for stage 3
- Less than 5% for stage 4
- Anemia may result, caused by chronic loss of blood - this may occur if the woman has ignored symptoms of prolonged or frequent abnormal menstrual bleeding.
- A perforation (hole) of the uterus may occur during a D and C or an endometrial biopsy.
Calling your health care provider
Call for an appointment with your health care provider if any of the above symptoms occur, particularly if you are a woman with associated risk factors, or if you have not had women’s health care examinations according to recommended schedules.
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 doctors. 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 lasting longer than 7 days
- Periods that recur every 21 days or less
- Reappearance of blood or staining after 6 months or more of no bleeding at all
by Martin A. Harms, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.