There are 3 types of uterine sarcoma:

• Leiomyosarcoma – this type of cancer begins in the smooth muscle cells that form the walls of the uterus.
• Endometrial stromal sarcoma – this type of cancer begins in the connective tissue cells of the stroma, which supports the lining of the uterus (the endometrium).
• Malignant Müllerian mixed tumour – this cancer can comprise
  • carcinosarcomas, which are a mixture of carcinomas (cancer of epithelial tissue, which is skin and tissue that lines or covers the internal organs, such as the endometrium) and sarcomas (cancer of connective tissue, such as bone, cartilage and fat)
  • adenosarcoma, which are a mixture of adenomas (cancers of gland-like cells) and sarcomas.

It can be difficult to tell the difference between a carcinosarcoma and an adenosarcoma.

Non-cancerous uterine conditions

There are several conditions of the uterus that are benign (non-cancerous). However, some – such as fibroids, endometriosis and adenomyosis – may cause uncomfortable symptoms and warrant treatment. Some others, such as endometrial hyperplasia, may develop into cancer, and your doctor may recommend treatment to lower the chances of it becoming cancerous.

Fibroids

Fibroids are common benign tumours that grow in the muscle of the uterus. They occur mainly in women in their 40s, and only rarely become cancer.

Usually, fibroids cause no symptoms and need no treatment. But depending on their size and location, they can cause bleeding, vaginal discharge and frequent urination. Women with these symptoms should see their doctor.

If fibroids cause heavy bleeding, or if they press against nearby organs and cause pain, the doctor can refer you to a gynaecologist, who may suggest surgery or other treatment.

As you reach menopause, fibroids are likely to become smaller. They can sometimes disappear.

Endometriosis

Endometriosis is most common in women in their 30s and 40s. It occurs especially in women who have never been pregnant. It occurs when endometrial tissue begins to grow on the outside of the uterus and on nearby organs.

Symptoms may include painful menstrual periods and abnormal vaginal bleeding. Sometimes, it can cause loss of fertility (cannot get pregnant).

Adenomyosis

Uterine adenomyosis happens because cells that normally line the inside of the uterus start to grow in the walls of the uterus. It is a benign condition that causes heavy, painful periods in women. It can occur along with endometriosis.

Endometrial hyperplasia

Endometrial hyperplasia is an increase in the number of cells in the lining of the uterus. It is most common in women older than 40.

Endometrial hyperplasia is not cancer, but it can sometimes develop into cancer.

Symptoms may include heavy menstrual periods, bleeding between periods and bleeding after menopause.

To prevent endometrial hyperplasia from developing into cancer, the doctor may recommend surgery to remove the uterus (hysterectomy) or treatment with hormones (progesterone) and regular follow-up curettage.