This condition is noncancerous and not deadly, but it can significantly affect your quality of life.
Endometriosis is not cancer and does not seem to increase the risk of uterine cancer.
Some studies have suggested that about 2% of people with endometriosis developuterine cancer.

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Below are the definitions and differences between endometriosis, endometrial cancer, and endometritis.
Theuterusis a small, pear-shaped female reproductive organ with a central cavity.
This cavity holds a fetus during pregnancy.
At the bottom of the cavity is the cervix, which leads into the vagina.
What Is Endometriosis?
The outer layer of the uterus, called themyometrium, is made of muscle.
The inner layer is theendometrium.
Once every 28 days or so, this lining sheds if an embryo hasn’t implanted.
The result is a menstrual period.
Endometriosisis when the cells lining the uterus’s central cavity grow outside the uterus.
Though it spreads outside the uterus, endometriosis is not cancerous and is not the same as endometrial cancer.
Endometrial cancer is when cells that line the inside of the uterus undergo changes and start growing.
Otherwise, it is unrelated to endometrial cancer or endometriosis.
Another common symptom of endometriosis and endometrial cancer is unusual discharge, including bleeding and spotting.
Butstage 4 endometriosisis severe and more likely to impact fertility (the ability to get pregnant).
Intestinal distress that develops during menstrual periods is another common symptom of endometriosis.
Causes
There are no clear causes for most cases of either endometriosis or endometrial cancer.
Endometriosis
There is no single risk factor that researchers believe directly causes endometriosis.
A surgeon will be able to see the growths and take samples to study under a microscope.
But stage 4 endometriosis is not the same as stage 4 endometrial cancer.
They are staged using different systems; these stages are defined differently and have different prognoses.
This system assigns points based on specific characteristics of the endometriosis lesions, as seen during surgery.
But the stage doesn’t necessarily correlate with symptoms or how much the disease affects the person.
Lesions are also classified as either deep or superficial.
There is usually also extensive scar tissue in the abdomen and signs of inflammation.
Treatments can help reduce the symptoms and problems due to stage 4 endometriosis.
Treatment includes:
Recurrence of Pain
There is no cure for endometriosis.
Surgery can relieve the pain of endometriosis, but this relief is temporary.
Within two years of surgery, 40%80% of people with endometriosis are in pain again.
Stage 4 Endometrial Cancer
Treatment for stage 4 endometrial cancer is aggressive.
Stage 4 endometrial cancer is deadly without treatment.
Summary
Stage 4 endometriosis is not endometrial cancer.
Treatment for endometriosis focuses on treating the symptomsrelieving the pain through medications, surgery, and other treatment options.
Endometrial cancer can also cause pelvic pain, irregular bleeding or discharge.
It can be felt as a lump or mass in the abdomen and can lead to unexplained weight loss.
Stage 4 endometrial cancer is not curable.
It has often spread too far for surgery to remove all the cancer.
About 20% of people diagnosed with distant endometrial cancer between 2011 and 2017 were alive five years later.
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