Endometrial Cancer (Uterine Cancer)

There are several categories of endometrial cancer, including: 

Endometrioid cancer.  This is by far the most common type. It starts in the glands of the endometrium. Under a microscope, these cancer cells look very similar to normal uterine lining (endometrium). Its seriousness varies from person to person. 

Serous cancer.  About 10% of people with endometrial cancer have this rare and fast-growing type of endometrial cancer. It tends to come back even if your doctor spots it early.

Clear cell carcinoma. This very rare type looks clear under a microscope, which is where it gets its name. This type accounts for less than 5% of cases of endometrial cancer. 

Grading Endometrial Cancer

If you get a diagnosis of type 1 or type 2 endometrial cancer, your doctor might talk to you about its grade” For most cancers, the grade (also called “differentiation”) is a number that tells you how abnormal your cancer cells look under a microscope. A lower number means the cancer cells are more normal-looking.

“Generally the higher the grade, the faster the tumor cells are dividing. Compared to low-grade tumors, high-grade tumors are more likely to spread and more likely to recur,” said Betty Suh-Bergmann, MD, chair of gynecologic oncology for Kaiser Permanente Northern California.

Here’s how endometrial cancer is graded:

Grade 1. Grade is considered type 1 endometrial cancer. With this grade, the cells of the cancer look very similar to normal cells.

Grade 2. Grade 2 cancers are also considered type 1, though they’re more likely to spread than Grade 1 cancers. With this type, the cancer cells look somewhat abnormal.

Grade 3. Grade 3 tumors are considered type 2 endometrial cancer. These cells look abnormal and are more likely to spread quickly. 

Endometrial Cancer Risk Factors

Endometrial cancer usually happens after menopause. More than 95% of endometrial cancer affects those over 40.  You have a higher risk for endometrial cancer if you:

• Got your first period early
• Went through menopause late
• Have obesity
• Have diabetes or high blood pressure
• Have few or no children
• Have a history of infertility, irregular periods, 
• Have polycystic ovary syndrome (PCOS) or abnormal cells in the endometrium (called endometrial hyperplasia)
• Have a family history of endometrial, colorectal, or breast cancer
• Are past menopause and have vaginal bleeding of any kind.
• Have irregular or unusually heavy bleeding between menstrual cycles
• Have Lynch syndrome, an inherited condition that raises the risk of many kinds of cancer
• Are Black

"Black women are at  higher risk of developing endometrial cancer and also dying of endometrial cancer compared to other races,” said Jeffrey How, MD, an assistant professor in the department of gynecologic oncology and reproductive medicine at the MD Anderson Cancer Center in Houston. This is true even when you consider things like  income, health care access, and education, but it’s not clear why.

If you’re taking the drug tamoxifen to treat or prevent breast cancer, you have a slightly higher risk of endometrial cancer. But if you’ve taken birth control pills, you’re only half as likely to have endometrial cancer after menopause.

Estrogen-only hormone replacement therapy increases your risk. So if you haven’t had a hysterectomy, you shouldn’t be taking estrogen-only hormone replacement therapy.

They’re rare, but ovarian tumors can make estrogen and increase your chances of endometrial cancer.

High-fat diets, especially those containing red meat, can increase the risk of cancer, including endometrial and colon cancer.

Endometrial Cancer Prognosis

Your outlook depends on how far your cancer has spread when you’re first diagnosed with it. To show the survival rates for endometrial cancer, the American Cancer Society uses a database that groups this type of cancer into three stages that describe how far it has spread:

• Localized means there’s no sign that your endometrial cancer has spread beyond your uterus.
• Regional means the disease has spread to nearby areas or lymph nodes.
• Distant means the cancer has spread to faraway parts of the body like your lungs, liver, or bones.

For localized endometrial cancer, the five-year relative survival rate is 96%. That means that people with this type of cancer are about 96% as likely as people who don’t have it to live for at least five years, on average, after they’re diagnosed.

The five-year relative survival rate for regional endometrial cancer is 71%. For distant endometrial cancer, it’s 20%.

Keep in mind that other things affect your outlook, like your age, general health, and how well endometrial cancer treatment works for you.

If you’ve just been diagnosed with endometrial cancer, you may have a better outlook than these numbers suggest. Treatments get better over time, and these numbers are based on people who were diagnosed and treated at least five years earlier.

Endometrial Cancer Prevention

Most endometrial cancer can’t be prevented. But there are certain things you can do that may lower your chances of getting it. 

Using hormonal birth control lowers the risk, but first talk with a doctor about possible pros and cons.

Being healthy overall, eating well, exercising, and watching your weight may help lower your risk.

Takeaways

Uterine cancer is cancer of the uterus, a female reproductive organ involved in menstruation and pregnancy.  The most common type is endometrial cancer, which affects the lining of the uterus. It most often happens after menopause. Fortunately, it grows slowly. With regular checkups, it’s usually found before it spreads very far. 

Endometrial Cancer FAQs

What is the alpha-beta ratio of endometrial cancer​?

This is a technical term doctors use to describe how sensitive a tumor is to radiation. The alpha-beta ratio can help determine the kind of radiation treatment you may need.  It’s calculated by a radiologist (a doctor who is an expert in medical imaging) specializing in cancer. The ratio is based on the risk of your cancer spreading (alpha) or returning (beta). A specialist may recommend fewer, but higher doses of radiation, or more frequent but smaller doses, depending on what type of endometrial cancer you have.

What percentage of endometrial thickness is cancer?

Doctors sometimes measure how thick the endometrium is using imaging tests. If you’re past menopause and your endometrial lining is thicker than 4-5 millimeters, your gynecologist may suggest a biopsy to check for cancer, says Kim.

But not all types of endometrial thickness (hyperplasia) raise your risk for cancer. The cancer risk for those with endometrial hyperplasia ranges from about 8% to 30%, depending on what type of cell changes show up in your endometrium.

 If you’re still getting your period, the thickness of your endometrial lining varies depending on where you are in your menstrual cycle. The lining thickens as you get closer to having your period. 

Does fluid in the endometrial cavity mean cancer​?

While it doesn’t necessarily mean you have cancer, your doctor may want to do a biopsy to check for cancer if you have fluid in your endometrial cavity (the hollow space in your uterus). Other possible causes include infection and hormonal imbalances. 

How fast does grade 3 endometrial cancer spread?

It is hard to know exactly how fast a particular tumor will grow. But generally, the higher the grade, the faster the tumor cells are dividing. High-grade tumors are more likely than low-grade ones to spread and to come back after treatment. People with high-grade tumors are more likely to need additional treatment after surgery, such as chemotherapy and/or radiation. 

Is endometrial cancer curable​?

This cancer is very curable when caught early.  “The vast majority of patients with Stage 1 endometrial cancers, which the vast majority of endometrial cancers, are cured,” says. Kim. 

The chances of long-term survival with endometrial cancer vary by type and stage. The most important factor for overall life expectancy is stage.