What is Endometrial Cancer?

Endometrial cancer is a malignant growth of cells of the uterus. This type of cancer may be called cancer of the womb, uterus or endometrium or endometrial cancer. Endometrium is the name given to the inner lining of the womb and it is these lining cells which become cancerous, hence the name endometrial cancer. Only women have a uterus, it is located in the pelvis. The endometrial lining provides a rich environment for attachment of a fertilised egg that grows into a foetus; the uterus expands massively during pregnancy. The innermost layer of the endometrial lining is shed every month that pregnancy does not occur - menstruation. Menstruation stops during the menopause which happens at around 50 years of age. Endometrial cancer is rare in women under 50 but is becoming more common. Endometrium is a hormone responsive tissue and the rate of cancer is higher in those who are exposed to high doses of oestrogen. Almost all are adenocarcinomas. Rare tumours which affect the uterus include sarcomas, tumours with a ‘squamous’ cell type and clear cell carcinomas. This guidance applies to all endometrial cancers except sarcomas.

The types of endometrial cancer that are adenocarcinomas include:

• Endometrioid adenocarcinoma – this is the commonest type with the best outlook
• Papillary serous carcinoma – a more aggressive type (15-20% of cases)
• Clear cell carcinoma –rare but can be very aggressive, this may occur in women whose mothers’ took diethylstilboestrol treatment during pregnancy in the 1960s.

The other type of cancer covered by the guidance is a mixture of glandular and ‘squamous’ cervical type cells called:

• Adenoacanthomas – these are rare and are often at a more advanced stage when diagnosed than endometrial endometrioid adenocarcinoma

Prevalence

6000 women are diagnosed with endometrial cancer every year in the UK. The outlook for women with this type of cancer is very good; about 75% of women affected will be alive 10 years later. This is because the disease causes symptoms at an early stage, allowing early diagnosis and treatment.

Amended April 2008