Screening for Endometrial cancer

August 2, 2011

Endometrial cancer begins in the endometrium, the inner lining of the uterus. Approximately 40,000 cancers of the endometrium are found each year. It is the most common gynecologic cancer; however, it has a relatively low death rate with fewer than 7,000 deaths every year. The peak incidence of endometrial cancer is between the ages of 55 and 65 years. Obesity, never bearing children (nulliparity), and a family history of endometrial cancer are risk factors. The other major risk factors are related to an abnormal balance between the hormones estrogen and progesterone. Estrogen causes growth of the cells that line the uterus and progesterone controls this growth. A prolonged period of stimulation of the lining of the uterus by high levels of estrogen results in more growth and a greater chance of cells changing into cancer. Therefore, any of the following may cause prolonged exposure of the endometrium to estrogen without the opposing effect of progesterone, thus increasing the risk for cancerous development. Age is a risk factor. The excessive use of estrogen alone without progesterones, tamoxifen use, late menopause, early onset of menses, and polycystic ovary syndrome can all result in more years of estrogen exposure, thus increasing the risk of the development of cancer. Hormone replacement therapy for women after menopause does result in some increased risk of endometrial cancer. The risk is very high when the estrogen is taken alone without the countering hormone progesterone. The addition of progesterone reduces the risk but does not eliminate it. Women who have a family history of breast or ovarian cancer are at increased risk, as are those who eat a diet high in animal fat. Women who are very obese may convert male hormones to estrone, a female hormone, in the fat cells, which can stimulate the endometrium and predispose it to cancer.

A woman’s risk is reduced, as stated above, by the use of progesterone therapy to counterbalance the estrogen therapy. Combination oral contraceptives decrease the risk of endometrial cancer. Menopause before the age of 49, normal weight, and a history of having multiple pregnancies also decrease the risk of endometrial cancer.

Low-risk women without symptoms do not require screening for endometrial cancer. For women at high risk, however, endometrial biopsy, dilation and curettage (where the lining is removed from the uterus), or vaginal ultrasound are all potential screening modalities. There is no evidence to justify screening low-risk women with no symptoms. It is important to note that if endometrial cells are noted in a Pap smear report in postmenopausal women or atypical endometrial cells are noted in a women at any age, she should have further investigation. A major symptom that should prompt a woman to seek a medical evaluation is unexplained bleeding after menopause. Some women over the age of 30, but not yet menopausal, who have spotting between periods, prolonged periods, or extremely heavy periods, should also be evaluated.

SEE ALSO: Cervical cancer, Ovarian cancer, Uterine cancer

Category: Cancer Screening