How Endometriosis and Endometrial Cancer Differ

Medically Reviewed by Carol DerSarkissian, MD on May 14, 2022
4 min read

Endometriosis and endometrial cancer are conditions that affect a woman's uterus, also called the womb. It's an organ in the lower belly where an unborn baby grows.

The two diseases share some things in common, such as causing cells to grow where they shouldn't. But there are key differences, too.

Endometriosis happens when the special tissue that normally lines your uterus, called the endometrium, starts to grow in other places.

You get endometrial cancer when cells of the endometrium become abnormal looking, grow out of control, and form a tumor. These cells may spread to other parts of the body and become tumors there, too.

One important way the two conditions differ: endometriosis is not cancer. But there is some early evidence endometriosis may slightly raise your chances of getting certain rare types of ovarian and endometrial cancer.

Endometriosis. It most often causes pain in your lower belly area, especially when you're having your period. That's because wherever the endometrial tissue develops, it often bleeds along with the lining of your uterus during your monthly period. Blood can build up in the area and cause swelling and pain. This can even scar some of your internal tissue, making it less healthy and flexible and causing still more pain.

Other symptoms of endometriosis include:

  • Painful menstrual cramps in your lower belly or lower back
  • Pain during sex
  • Pain when you pee or have a bowel movement during your period
  • Difficulty getting pregnant
  • Heavy bleeding during your period
  • Vaginal bleeding, spotting, or bloody urine between periods

Endometrial cancer. You might notice similar symptoms if you have endometrial cancer. Unusual bleeding, for example, whether during or between periods, is common in about 90% of women with the disease. Unusual belly pain and swelling are more common in later stages of this cancer.


Endometriosis. It's possible for girls to get endometriosis as soon as they've started having a period. But it's more likely to happen once you get into your 30s and 40s. Your chances go up more if:

  • Other family members have had it.
  • Your period lasts longer than 7 days.
  • You start your period very young (under 12).

It typically takes years to diagnose endometriosis, so talk to your doctor if you notice symptoms like pain, heavy bleeding, bad cramps, bloating, and spotting between periods. It affects up to 10% of women in their reproductive years.

Endometrial cancer. It's the most common cancer that affects women's reproductive health. The average age for diagnosis is 60 and it's uncommon in women under 45. 


Endometriosis. It typically appears on the outside of your uterus, on your ovaries, or in the fallopian tubes -- the pathways that transfer your eggs. But it can start anywhere. In rare cases, endometrial tissue can spread to your lungs, eyes, skin, or brain.

Endometrial cancer. It can spread to other parts of your body if you don't catch and treat it early. This usually starts with nearby tissue like the lymph nodes, liver, and the lining of the abdomen (peritoneum), but may spread further to the lungs, adrenal glands, blood, bones, and the brain.

For both conditions, your doctor will want to examine you and get a full medical history and description of any symptoms. They may also ask you to get imaging tests such as an X-ray, CT scan, ultrasound, MRI, or PET scan.

To make a final diagnosis for endometriosis and endometrial cancer, your doctor will need to do a procedure called a biopsy. They take a small piece of tissue from your body to examine under a microscope.

For this procedure, the doctor may send a small camera and tool through a tube that goes into your belly or from your vagina into the uterus.

Endometriosis. The point of treatment is to lessen the pain of the disease. Hormones, pain drugs, and, in more serious cases, surgery, can help do this.

Your symptoms might improve during pregnancy. That's because you won't have your period and also because levels of the hormone progesterone rises. But they will likely return after you give birth or finish breastfeeding.

If you have severe disease, your doctor might suggest surgery to remove endometrial or scar tissue or your entire uterus (hysterectomy). That could help symptoms, but it won't necessarily cure the condition.

Endometrial cancer. Treatment depends on a number of things, including the type of endometrial cancer you have and how much it has spread.

Surgery is almost always the first line of treatment. The doctor will try to remove as much of the tumor as possible as well as the tissue that has cancer cells that could continue to grow. This typically means removal of the uterus, fallopian tubes, and ovaries, and might also include lymph nodes in the area.

A lab will usually test the tissue the surgeon removes to help figure out the type of cancer and how far it may have spread. The results can help determine whether you need further cancer treatment like radiation or chemotherapy.

Because hormones like estrogen are often linked to this cancer, hormone blocking medications also might help.