Cancer of the Uterus Endometrial Cancer

What is endometrial cancer?

Most uterine cancers develop from cells in the endometrium. The endometrium is the inside lining of the womb (uterus) and this cancer is called endometrial cancer. It is an adenocarcinoma. Cancers developing from muscle cells in the myometrium (uterine sarcomas) and mixed tumours (carcinosarcomas) are rare and are not dealt with further in this leaflet. Cancer of the cervix is quite different to uterine cancer and is dealt with in a separate leaflet called Cervical Cancer.

The rest of this leaflet deals only with endometrial cancer.

What is the womb (uterus)?

The uterus is in your lower tummy (abdomen) and behind your bladder. The inside of your uterus is where a baby grows if you become pregnant. The inside lining of your uterus is called the endometrium. This builds up and is then shed each month as a period in women who have not yet gone through the menopause. The thick body of the uterus is called the myometrium and is made of specialised muscle tissue.

The lowest part of your uterus is the neck of the womb (cervix) which pushes just into the top part of your vagina.

How common is endometrial cancer?

Each year around 9,700 women in the UK develop cancer of the inside lining of the womb (uterus), known as endometrial cancer. It is the fourth most common cancer in women in the UK. Most cases develop in older women over the age of 50. It rarely develops in women under the age of 50. The peak age range for developing endometrial cancer is between the ages of 75 and 79.

What causes endometrial cancer?

A cancerous tumour starts from one abnormal cell. The exact reason why a cell becomes cancerous is unclear. It is thought that something damages or alters certain genes in the cell. This makes the cell abnormal and multiply out of control. See the separate leaflet called Causes of Cancer for more details.

Risk factors for endometrial cancer

There are risk factors which are known to increase the risk of endometrial cancer developing. These include the following:

Increased exposure to oestrogen

Oestrogen is the main female hormone. Before the menopause the changing level of oestrogen together with another hormone, progesterone, causes the endometrium to build up each month and then be shed as a period. It is thought that factors which lead to prolonged higher-than-usual levels of oestrogen, or increased levels of oestrogen not being balanced by progesterone, may somehow increase the risk of endometrial cells becoming cancerous. These include:

• If you have never had a baby. This is because your womb (uterus) has never had a rest from the rise of oestrogen that happens in the course of a normal monthly cycle.
• If you are overweight or obese. This is because fat cells make oestrogen.
• If you have certain rare oestrogen-producing tumours.
• If you have a late menopause (after the age of 52) or started periods at a young age. This is because you will have more monthly menstrual cycles.

Endometrial hyperplasia

This is a non-cancerous (benign) condition where the endometrium builds up more than usual. It can cause heavy periods or irregular bleeding after the menopause. Most women with this condition do not develop cancer but the risk is slightly increased.

Tamoxifen

Tamoxifen is a medicine which is used in the treatment of breast cancer. The risk of developing endometrial cancer from tamoxifen is very small - about 1 in 500. However, the benefits of taking tamoxifen usually outweigh the risks.

• Diabetes.
• Polycystic ovary syndrome.

Genetic factors

'Genetic' means that a condition is passed on through families through special codes inside cells called genes. Most cases of endometrial cancer are not due to genetic or inherited (hereditary) factors. However, in a small number of cases, a faulty gene (which can be inherited) may trigger the disease. This disorder is called hereditary nonpolyposis colon cancer (HNPCC).

Diabetes

There is a small increased risk in women with diabetes.

Polycystic ovary syndrome

There is a very slight increased risk in women with polycystic ovary syndrome.

Women who take the combined oral contraceptive (COC) pill actually have a lower risk of developing endometrial cancer.

Type and grade of endometrial cancer

Most cases of endometrial cancer are called endometrioid adenocarcinomas. These arise from cells which form the glandular tissue in the lining of your endometrium. A sample of cancerous tissue can be looked at under the microscope. By looking at certain features of the cells the cancer can be graded.

• Grade 1 - is a low grade. The cells look reasonably similar to normal endometrial cells. The cancer cells are said to be well differentiated. The cancer cells tend to grow and multiply quite slowly and are not so aggressive.
• Grade 2 - is a middle grade.
• Grade 3 - the cells look very abnormal and are said to be poorly differentiated. The cancer cells tend to grow and multiply quite quickly and are more aggressive.

The grade of cancer is different to the stage, which is explained further in the outlook (prognosis) section below.

There are also some rarer types of endometrial cancer.

Endometrial cancer symptoms

In most cases the first symptom of cancer of the inside lining of the womb (uterus) - known as endometrial cancer - is abnormal vaginal bleeding such as:

• Vaginal bleeding past the menopause. This can range from spotting to more heavy bleeds. This is the most common symptom of endometrial cancer.
• Bleeding after having sex (postcoital bleeding).
• Bleeding between normal periods (intermenstrual bleeding) in women who have not gone through the menopause.

Early symptoms that occur in some cases are:

• Pain during or after having sex.
• Vaginal discharge.
• Pain in your lower tummy (abdomen).

All the above symptoms can be caused by various other common conditions. However, if you develop any of these symptoms, you should see your doctor.

Note: a cervical screening test does not screen for endometrial cancer.

In time, if the cancer spreads to other parts of the body, various other symptoms can develop.

How is endometrial cancer diagnosed and assessed?

To confirm the diagnosis

A doctor will usually do a vaginal examination if you have symptoms which may be due to cancer of the inside lining of the womb (uterus) - known as endometrial cancer. He or she may feel an enlarged womb. It is likely you will need to have a further test to confirm the diagnosis - usually one of the following:

• Ultrasound scan of your womb. This is usually the first test that is done. An ultrasound scan is a safe and painless test which uses sound waves to create images of organs and structures inside your body. It is most commonly used in pregnant women.
• Endometrial sampling. In this procedure, a thin tube is passed into your womb. By using very gentle suction, small samples of your endometrium can often be obtained. This is done in the outpatient clinic, without an anaesthetic. The sample (biopsy) is looked at under the microscope to look for any abnormal cancer cells.
• Hysteroscopy. In this procedure, a doctor uses a hysteroscope, which is a thin telescope that is passed through the neck of your womb (cervix) into your uterus. The doctor can see the lining of your uterus and take samples of any abnormal-looking areas. This can also be done without an anaesthetic.

Assessing the extent and spread

If endometrial cancer is confirmed then further tests may be advised to assess if the cancer has spread. For example, a computerised tomography (CT) scan, a magnetic resonance imaging (MRI) scan, a chest X-ray, blood tests, an examination under anaesthetic of the uterus, bladder or rectum, or other tests. This assessment is called staging of the cancer. The aim of staging is to find out:

• How much the tumour has grown and whether it has grown into other nearby structures such as the cervix, bladder or rectum.
• Whether the cancer has spread to local lymph glands (nodes).
• Whether the cancer has spread to other areas of the body (metastasised).

Finding out the stage of the cancer helps doctors to advise on the best treatment options. It also gives a reasonable indication of outlook (prognosis) - see below. See also the separate leaflet called Stages of Cancer for more details.

Associated conditions testing

Lynch syndrome is an inherited condition which increases your risk of endometrial and some other cancers, including bowel cancer. Most women diagnosed with cancer of the womb lining do not have Lynch syndrome. However, if you do have it, treatment and careful follow-up screening can reduce your chance of developing other cancers associated with Lynch syndrome.

That's why guidance from NICE recommends that if you're diagnosed with endometrial cancer, you should also be offered testing for Lynch syndrome.

Endometrial cancer treatment options

Surgery is the main treatment for cancer of the inside lining of the womb (uterus) - known as endometrial cancer. Radiotherapy or chemotherapy are also used in some circumstances. The treatment advised for each case depends on various factors such as the stage of the cancer (how large the cancer is and whether it has spread) and your general health.

Surgery

An operation to remove your uterus (hysterectomy) and ovaries is a common treatment. It is common for your Fallopian tubes and both ovaries to be removed as well. Many operations are now performed by a keyhole procedure (laparoscopically). If the cancer is at an early stage and has not spread then surgery alone can be curative.

If the cancer has spread to other parts of the body, surgery may still be advised, often in addition to other treatments. Even if the cancer is advanced and a cure is not possible, some surgical techniques may still have a place to ease symptoms - for example, to relieve a blockage of the bowel or urinary tract which has been caused by the spread of the cancer.

Radiotherapy

Radiotherapy is a treatment which uses high-energy beams of radiation which are focused on cancerous tissue. This kills cancer cells or stops cancer cells from multiplying. Radiotherapy alone can be curative for early-stage endometrial cancer and may occasionally be an alternative to surgery. In some cases radiotherapy may be advised in addition to surgery.

Even if the cancer is advanced and a cure is not possible, radiotherapy may still have a place to ease symptoms. For example, radiotherapy may be used to shrink secondary tumours which have developed in other parts of the body and are causing pain.

Chemotherapy

Chemotherapy is a treatment of cancer using anti-cancer medicines. They kill cancer cells, or stop them from multiplying. Chemotherapy is not a standard treatment for endometrial cancer but may be given in certain situations (usually in addition to radiotherapy or surgery).

Hormonal treatments

Treatment with progesterone is used in some types of endometrial cancer. It is generally not used in the initial treatments but may be considered if the cancer spreads or comes back after those treatments.

Treatment aims

You should have a full discussion with a specialist who knows your case. They will be able to give the pros and cons, likely success rate, possible side-effects and other details about the various possible treatment options for your type of cancer. You should also discuss with your specialist the aims of treatment. For example:

• In most cases, treatment aims to cure the cancer. Most cases of endometrial cancer are diagnosed at an early stage. There is a good chance of a cure if it is treated in the early stages. (Doctors tend to use the word remission rather than the word cured. Remission means there is no evidence of cancer following treatment. If you are in remission, you may be cured. However, in some cases a cancer returns months or years later. This is why doctors are sometimes reluctant to use the word cured.)
• In some cases, treatment aims to control the cancer. If a cure is not realistic, with treatment it is often possible to limit the growth or spread of the cancer so that it progresses less rapidly. This may keep you free of symptoms for some time.
• In a few cases, treatment aims to ease symptoms. For example, if a cancer is advanced then you may require treatments such as painkillers or other treatments to help keep you free of pain or other symptoms. Some treatments may be used to reduce the size of a cancer, which may ease symptoms such as pain.

Endometrial cancer prognosis

The outlook (prognosis) depends on the stage at which endometrial cancer is picked up. There is an excellent chance of a cure if cancer of the inside lining of the womb (uterus) is diagnosed and treated when the disease is at an early stage.

This is when the cancer is confined to the womb and has not spread. Many cases are diagnosed at an early stage because abnormal vaginal bleeding often develops at an early stage of the disease and alerts women (and their doctors) to the possibility of cancer. This is why it is very important to see your doctor if you have any abnormal bleeding, particularly bleeding between periods or after the menopause.

For women who are diagnosed when the cancer has already spread, a cure is less likely but still possible. Even if a cure is not possible, treatment can often slow down the progression of the cancer.

Prognosis according to stage in the UK

Remember prognosis takes lots of different factors into account, not just the stage, so for more accurate information about your case, you should ask the specialist doctor treating you personally. For a general idea:

• Stage 1: the cancer is contained within the muscle wall of the womb. Most women can be completely cured. 92 out of 100 women diagnosed at Stage 1 will live for five years or more.
• Stage 2: the cancer has spread into the neck of the womb (cervix). More than 74 out of 100 women diagnosed at Stage 2 will live for five years or more.
• Stage 3: the cancer has spread outside the womb, but only as far as the tissues around the womb. 48 of 100 women diagnosed at Stage 3 will live for five years or more.
• Stage 4: the cancer has spread further around the body. Around 15 out of 100 women diagnosed with Stage 4 cancer will be alive after five years.

Overall, taking all stages into account, more than 72 out of every 100 women diagnosed with endometrial cancer in England and Wales will live 10 years or more after being diagnosed.

The treatment of cancer is a developing area of medicine. New treatments continue to be developed and the information on outlook above is very general. The specialist who knows your case can give more accurate information about your particular outlook and how well your type and stage of cancer are likely to respond to treatment.