Endometrial cancer is the most common type of gynecological cancer. It affects the uterus (womb) — the organ that holds a fetus while you are pregnant. Endometrial cancer occurs when the cells in your endometrium (the inner lining of your uterus) undergo changes and become cancerous, forming a tumor.
What causes endometrial cancer?
Experts don’t fully understand why this condition develops. However, research has found that your risk of developing endometrial cancer rises the more you are exposed to estrogen, a reproductive hormone.
Many endometrial cancer risk factors increase the amount of estrogen your uterus is exposed to and can therefore increase your chances of developing this disease. These risk factors include:
- Using hormone replacement therapy (HRT) medications that contain estrogen but not progesterone
- Taking tamoxifen, a hormone medication used to treat breast cancer
- Going a long time in between menstrual periods
- Starting your menstrual period early (before you turn 12) or going through menopause late (after age 50)
- Never having been pregnant
- Being obese
- Being diagnosed with endometrial polyps or polycystic ovary syndrome (PCOS)
- Having diabetes or metabolic syndrome
Some other health conditions can also make it more likely that you will develop endometrial cancer. People with high blood pressure, gallbladder disease, colon cancer, and breast cancer have a higher risk. Additionally, your chances of endometrial cancer are greater if your mother, sister, or child has had this disease.
Endometrial cancer symptoms
Endometrial cancer can lead to signs like:
- Vaginal bleeding outside of your menstrual period or after you have gone through menopause
- Changes in vaginal discharge
- Discomfort or pain while urinating
- Painful sex
- Aches and pains in the pelvis (the lower part of the trunk)
If you think that you might be experiencing symptoms of endometrial cancer, tell your doctor. Various tests can help determine whether there are any abnormal cells in your uterus. Your doctor may recommend tests like a biopsy (removal of a small piece of endometrium), hysteroscopy (a procedure in which a thin tube with a camera on the end is inserted into the uterus), or imaging tests.
The stages and types of endometrial cancer
When diagnosing endometrial cancer, your doctor will also determine your cancer’s stage. This describes how far in your body your cancer has spread:
- Stage I — Cancer is only located in the uterus, and not any other parts of the body.
- Stage II — Cancer is in the uterus and has also spread to the cervix.
- Stage III — Cancer cells have spread to other locations in the pelvis, including the outer layer of the uterus, ovaries, or vagina.
- Stage IV — Cancer is found in further locations in the body, such as the bladder, intestines, or organs in the abdomen.
Your doctor will also assign a grade to your tumor. This describes how abnormal the cancer cells look. Grade 1 and grade 2 cancers are low-risk and unlikely to spread, while grade 3 cancer is considered high-risk and tends to grow more aggressively.
There are also many types and sub-types of endometrial cancer. The most common type is adenocarcinoma, and most cancers within this category belong to a sub-type called endometrioid cancer. These tumors are usually low-grade and slow-growing. Certain types of endometrial cancer, such as clear-cell carcinoma, mucinous adenocarcinoma, serous adenocarcinoma, and undifferentiated carcinoma, are rarer but tend to grow more quickly.
Endometrial cancer treatments
Most people with endometrial cancer are first treated with surgery. This often involves a hysterectomy (removal of the uterus) and may also include taking out nearby tissues, such as the ovaries, cervix, and lymph nodes.
After surgery, you may need to undergo radiation therapy, in which high-energy beams or particles are used to kill any remaining cancer cells. Radiation therapy is most often recommended for people with higher-stage or higher-grade endometrial cancer or people who have a high chance of having their cancer return.
Medication for endometrial cancer may include a couple of different options:
- Chemotherapy — These drugs can destroy cancer cells or prevent them from growing and forming new cancer cells. Most people with endometrial cancer receive multiple types of chemotherapy drugs.
- Hormone therapy — Because endometrial cancer can be fueled by hormones like estrogen, hormone therapy may be needed. These medications lower hormone levels in the body or prevent hormones from feeding cancer cells.
- Targeted therapy — Targeted therapy drugs can block endometrial cancer cells while ignoring the normal, healthy cells in your body. They are more often given to people with more advanced-stage endometrial cancer (stage III or stage IV).
Your cancer stage, tumor grade, whether your cancer cells respond to the hormone progesterone, and your age and overall health all help determine your treatment plan. These factors also help determine your likelihood of having a good prognosis (outcome).
What is the outlook for endometrial cancer?
If you have endometrial cancer, your prognosis is primarily determined by how far your cancer cells have spread:
- Cancer is only located in the uterus — About 95% of people will survive the effects of their cancer for five years or more.
- Cancer cells are found in nearby lymph nodes — Nearly 70% of people will survive their cancer for at least five years.
- Cancer has metastasized to distant parts of the body — About 52% of people will survive the effects of their cancer for at least five years.
Your individual prognosis may differ from these estimates based on the characteristics of your body and your cancer. If you want a better idea of what to expect, talk to your doctor.
Endometrial cancer can be a serious condition, but it is very treatable if it is caught early. Go in for a visit with your gynecologist if you think you might be experiencing cancer symptoms.
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