What is Endometrial Cancer?
Endometrial cancer forms in the tissue lining the uterus. It is one of the most common cancers in American women. Endometrial cancer is one type of uterine cancer. There are other cells in the uterus that can become cancerous, including muscle or myometrial cells. These become sarcomas, which are less common. Most endometrial cancers are adenocarcinomas or cancers that start in cells that make mucus and other fluids
Women who use estrogen without progesterone, especially for long periods of time, are at an increased risk for endometrial cancer. Women taking the drug tamoxifen to prevent or treat breast cancer also have an increased risk.
Obese women have higher levels of estrogen in their bodies, which also puts them at higher risk for this disease. Women who have had an inherited form of colorectal cancer have a higher risk of developing uterine cancer than other women.
Risk Factors, Signs and Symptoms
While the clear causes of Endometrial Cancer are unknown, there are risk factors that are proven to be linked with the disease. Following is a list of known factors:
- Age and Diet - The risk of endometrial cancer goes up as a woman gets older. Women who have a diet high in animal fat are also at risk for developing Endometrial Cancer.
- Breast or Ovarian Cancer - Women who have had breast cancer or ovarian cancer may have a higher risk of getting endometrial cancer.
- Diabetes - Some studies suggest that diabetes could be a risk factor.
- Earlier Pelvic Radiation Therapy - Radiation can damage the DNA of cells. This could increase the risk of developing a second type of cancer.
Diagnosis and Staging
Endometrial cancer is often detected at an early stage. This is because it can present as heavy bleeding or bleeding with menses in premenopausal women or uterine bleeding after menopause. Other symptoms include difficult or painful urination, pain in the pelvic area, and pain during intercourse.
When this cancer is found early, removing the uterus, the ovaries, and fallopian tubes often eliminates all of the cancer. Sometimes, lymph nodes have to be removed at the time of surgery in order to fully assign the cancer a stage. The doctor may perform one or more of the following procedures to determine if cancer is present:
The doctor feels the pelvic area to check the vagina, uterus, bladder, and rectum for lumps or changes in shape and size. The doctor inserts a speculum into the vagina to see the upper part of the vagina and cervix.
The doctor may take cells from the cervix and upper vagina, and lab checks for abnormal cells. This test can detect cancer of the cervix, but cells from the uterus usually do not show up on a Pap test.
Sound waves and a computer are used to create a picture of the uterus, which can show tumors and abnormalities. If the endometrium looks too thick, the doctor will do a biopsy.
The doctor removes samples of tissue from the uterine lining. This is usually done in the doctor’s office, but in some cases, the patient needs a dilation and curettage (D & C). This is usually done as same-day surgery. A pathologist then checks the samples for cancer cells.
Stages of Endometrial Cancer
If endometrial cancer is diagnosed, the doctor needs to know the stage, or extent, of the disease to plan the best treatment. Staging is a careful attempt to find out whether the cancer has spread, and if so, to what parts of the body. If your cancer spreads to the bone, visit our bone metastases page.
- Stage I - The cancer is only in the body of the uterus. It is not in the cervix.
- Stage II - The cancer has spread from the body of the uterus to the cervix.
- Stage III - The cancer has spread outside the uterus, but not outside the pelvis (and not to the bladder or rectum). Lymph nodes in the pelvis may contain cancer cells.
- Stage IV - The cancer has spread into the bladder or rectum. Or it has spread beyond the pelvis to other body parts.
There are several treatment options for endometrial (uterine) cancer. Most women are treated with surgery. Some have radiation, and a smaller number have hormonal therapy. Hormonal therapy and upfront radiation therapy are used primarily in patients who are not surgical candidates. Some patients receive a combination of the following therapies:
Most women with uterine cancer require surgery to remove the uterus, called a hysterectomy. This is done through an incision in the abdomen. The doctor also usually removes both ovaries and both fallopian tubes called a bilateral salpingo-oophorectomy. The doctor may also remove nearby lymph nodes to check for cancer.
If cancer cells have not spread beyond the endometrium, the patient may not need any other treatment.
A large machine directs external radiation at the tumor area and uses high-energy rays to kill cancer cells. Internal radiation therapy is also used to treat uterine cancer. Tiny tubes containing radioactive substance are inserted through the vagina and left in place for a few days. The patient stays in the hospital during this treatment and may not be allowed visitors during this time to protect others from radiation exposure. Some patients need both external and internal radiation.
This treatment involves substances that prevent cancer cells from getting the hormones they need to grow. If the uterine tissue has estrogen and progesterone receptors, the patient is more likely to respond to hormone therapy. Hormone therapy is a type of progesterone taken as a pill. It can affect cancer cells throughout the body. Doctors may use this therapy for patients who are unable to have surgery or radiation, or for patients with uterine cancer that has spread or returned.
Follow-up care after treatment for uterine cancer is an important part of the overall treatment plan. Even when there are no longer any signs of cancer, the disease sometimes returns because undetected cancer cells remained somewhere in the body after treatment.
Your doctor will monitor your recovery and check for recurrence of the cancer. Checkups help ensure that any changes in your health are noted and treated if needed. Checkups may include a physical exam, a pelvic exam, x-rays, and laboratory tests.
Chemotherapy uses drugs to kill cancer cells. Chemotherapy is given to patients with “high-grade” (such as clear cell and serous), Stage I and II endometrial cancer. Chemotherapy is also given to patients with Stage III and IV endometrial cancer and if endometrial cancer returns. It is usually given through a vein. Most often, you will get a combination of 2 different drugs.
Immunotherapy uses a person’s own immune system to recognize and attack cancer cells. The first drug of this type approved for endometrial cancer patients is the PD-1 (checkpoint) inhibitor, pembrolizumab (Keytruda®). Keytruda can be used for people with advanced endometrial cancer that tests positive to MSI-high or dMMR. It can also be used in combination with the targeted therapy lenvatinib (Lenvima®) for people with advanced endometrial cancer that tests negative to MSI-high or dMMR, after other treatment has been tried.