Endometrial cancer — the most common type of uterine cancer — begins in the endometrium, or the lining of the uterus. It’s also the most common gynecologic cancer, affecting about 62,000 women in the U.S. each year.
Endometrial cancer is usually diagnosed early
“Most women with endometrial cancer present with abnormal vaginal bleeding,” says Douglas A. Levine, MD, director of gynecologic oncology at NYU Langone’s Perlmutter Cancer Center. In fact, according to the National Cancer Institute (NCI), an analysis of 129 studies with more than 40,000 women found that 90 percent of post-menopausal women diagnosed with endometrial cancer experienced vaginal bleeding before their diagnosis.
If you are pre-menopausal, you may experience abnormal bleeding as too-frequent periods, excessive flow, or bleeding between periods. “If a woman soaks more than five pads in a day, that’s really heavy bleeding,” says Anna Beavis, M.D., M.P.H., assistant professor of Gynecology and Obstetrics at Johns Hopkins University.
Because women present with abnormal vaginal bleeding, two-thirds of endometrial cancers are diagnosed at an early stage and the prognosis is generally good.
“The standard treatment is a hysterectomy to remove the uterus and usually the ovaries, cervix, and fallopian tubes,” says Dr. Levine. According to the NCI, the five-year survival rate for women with localized endometrial cancer is 95 percent.
Although abnormal vaginal bleeding is a key symptom of endometrial cancer, it’s also associated with less serious conditions, such as fibroids, polycystic ovary syndrome (PCOS), or polyps in the lining of the uterus, Dr. Beavis tells HealthCentral.
Vaginal bleeding can also occur in post-menopausal women because the vagina naturally atrophies — meaning it becomes dry and delicate — due to lack of estrogen. In the study cited above, only about 9 percent of women who went to the doctor because of bleeding were eventually diagnosed with endometrial cancer. So, while abnormal bleeding should prompt a visit to your doctor, don’t panic. You probably do not have endometrial cancer.
What are the risk factors for endometrial cancer?
There are several key factors that may increase your risk of endometrial cancer.
“About 50 percent of endometrial cancers are thought to be directly attributable to being overweight or obese,” says Dr. Beavis. In fact, endometrial cancer is one of the cancers most directly related to obesity. Not only do obese women have a 2.4 to 4.5 times greater risk of being diagnosed with endometrial cancer than normal weight women, they also face additional illness and risk of death from obesity-related heart disease.
“Hormone replacement therapy (HRT) can also increase your risk,” Dr. Beavis says. “If you’re taking HRT for symptoms like hot flashes, you have to take both progesterone and estrogen.”
Other risk factors include endometrial hyperplasia, a precancerous condition that may develop in women who are overweight or obese or who have PCOS. A small subset (2 to 5 percent) of endometrial cancers might be related to a genetic condition called Lynch syndrome that puts you at risk for developing endometrial and other types of cancer. And, of course, age is a risk factor for developing any cancer. The average age for women diagnosed with endometrial cancer is 62.
How is endometrial cancer diagnosed and staged?
Your gynecologist will examine you and ask questions about your bleeding to determine if a biopsy is appropriate. During a biopsy, says Dr. Levine, your doctor will take a sample of tissue from the inside of your uterus with a small device that looks like a straw. A pathologist will look at the tissue under a microscope and confirm whether you have cancer, pre-cancer, or a non-cancer cause of bleeding, he says.
If you cannot undergo a biopsy, your physician may perform dilation and curettage (D&C) under anesthesia. She will dilate (open) the cervix and scrape out a sample of the uterine lining to make sure there are no cancer cells.
“This also allows us to do a hysteroscopy, which uses a small camera to look inside the uterus for masses, fibroids, or polyps,” says Dr. Beavis. “It’s a little more in depth.”
If the pathologist confirms endometrial cancer, your gynecologic oncologist will remove your uterus, cervix, ovaries, and fallopian tubes and sample nearby lymph nodes to see if the cancer has spread, a process called staging. Imaging tests, such as a PET scan, can also help determine if your cancer has spread.
In stage 1 endometrial cancer, the tumor is confined to the uterus. If you have stage 2 cancer, it has spread to the cervix. Stage 3 means your cancer has further spread to the ovaries, fallopian tubes, vagina, or lymph nodes, but is still contained in the pelvis. Metastatic endometrial cancer (stage 4) involves other organs, most likely the bladder, bowel, or other lymph nodes in the groin or abdomen.
Oncologists also categorize endometrial tumors as low risk (grades 1 and 2) and high risk (grade 3). The stage and risk level of your cancer determine whether you need additional treatment after surgery.
“We also test tumors for markers that may indicate the patient may have Lynch syndrome,” says Dr. Beavis. “If the tumor has these markers, then we refer the patient for genetic testing.”
If you have endometrial cancer, seek care from a gynecologic oncologist who is trained in both removing these cancers and treating patients following surgery.
“Endometrial cancer is highly curable and is usually caught early, so it’s a favorable cancer overall,” says Dr. Levine. “The key is to bring abnormal bleeding to the attention of your gynecologist.”