Cancer of the uterus

Cancer of the uterus is the most common gynaecological cancer affecting women in New Zealand. Most cancers of the uterus are cancers of the lining of the uterus (the endometrium). Cancers can also develop in the muscle layers of the uterus. Knowing which type of cancer you have is important because it affects the decisions you and your doctor will make about treatment.

Adenocarcinoma of the endometrium

An adenocarcinoma is a cancer that starts in glandular tissue. Most women who are diagnosed with cancer of the uterus have this type of cancer.

Other types of cancer of the uterus

The less common types are adenosquamous carcinomas, papillary serous carcinomas and, rarely, clear cell carcinomas or uterine sarcomas. These are called high-risk cancers because they are more likely to spread.

Causes of cancer of the uterus

The exact cause of cancer of the uterus is not known. Some things seem to put women at more risk:

  • being over 50 years of age

  • being very overweight (obese)

  • never having been pregnant

  • endometrial hyperplasia: this is a non-cancerous condition where the lining of the womb becomes thicker

  • menopause

  • high blood pressure

  • diabetes

  • a family history of uterus, breast or bowel cancer: if you think you are at risk you should discuss this with your doctor

  • being on oestrogen hormone replacement therapy without progesterone.

Uterine cancer is not caused by sexual activity and cannot be passed on this way.

Remember, most women who have known risk factors do not get cancer of the uterus. Many women who do get cancer of the uterus have none of these risk factors.

How common is cancer of the uterus?

In New Zealand each year, around 400 women are diagnosed with cancer of the uterus. It is more common in women over the age of 50 than younger women.