What is radiotherapy?

Radiotherapy uses high-energy rays to destroy cancer cells. For vulval cancer this treatment is usually given from a machine outside the body (external radiotherapy). Sometimes it is also given by putting a radioactive source inside the body (internal radiotherapy or brachytherapy).


Radiotherapy may be given with chemotherapy. Doctors call this chemoradiation. The chemotherapy drugs can make the cancer cells more sensitive to radiotherapy.

The chemotherapy drug most commonly used is cisplatin. It is usually given once a week throughout your radiotherapy.

The side effects of chemoradiation are similar to radiotherapy side effects. But they can be more severe. Your doctor, radiographer or specialist nurse can give you more information about chemoradiation and the possible side effects of treatment.

When radiotherapy is used for vulval cancer

You may have radiotherapy:

  • before surgery, to try to shrink the cancer and make a smaller operation possible
  • after surgery, to reduce the risk of the cancer coming back – it may be used if the cancer was not completely removed, or if there was cancer in the lymph nodes
  • if you cannot have surgery
  • if vulval cancer has come back or spread.

Before your radiotherapy, your radiotherapy team will explain what your treatment involves and how it may affect you.

We have more information about what happens before and after radiotherapy, and questions you may want to ask.

If the cancer is advanced, the main aim of radiotherapy may be to improve quality of life by shrinking the tumour and reducing symptoms. This is known as palliative radiotherapy.


Radiotherapy to the pelvis can affect your fertility. If you would like to have children in the future, your cancer doctor can refer you to a fertility specialist before treatment begins. They can talk through possible fertility options with you.

Having external radiotherapy

Radiotherapy for vulval cancer is usually external. You usually have external radiotherapy as an outpatient once a day from Monday to Friday, with a rest at the weekend. Each session of treatment takes a few minutes.

The number of treatments you have will depend on the type and size of the cancer. The whole course of treatment for vulval cancer will usually last a few weeks.

Support from Macmillan

Macmillan is here to support you. If you would like to talk, you can:

Internal radiotherapy

Occasionally internal radiotherapy is given, in combination with external radiotherapy.

For internal radiotherapy, your doctor will insert a radioactive source directly into the cancer. This gives a high dose of radiotherapy to the tumour. As the radiation does not travel far, your surrounding organs will not be affected.

Side effects of radiotherapy

You may develop side effects over the course of your treatment. These usually improve over a few weeks or months after treatment finishes.

Your doctor, nurse or radiographer will discuss this with you, so you know what to expect. Let them know about any side effects you have during or after treatment. There are often things that can help.

The side effects of radiotherapy are made worse by smoking. If you smoke, stopping smoking will help.

Skin irritation

You may find the skin around your vulva and groin becomes dry and irritated. Your radiographer or specialist nurse will advise you on how to look after your skin during treatment.

Your specialist can prescribe cream to help soothe the soreness. Use lukewarm water to wash the area, and gently pat the area dry with a soft towel. You should not use talcum powder or perfume, as these can cause irritation.

You may lose some of your pubic hair. It usually grows back after treatment, but may be thinner than it was before.


Tiredness is a common side effect and may continue for some months after treatment is over. During treatment, you may need to rest more than usual. But it is good to do gentle exercise, such as walking, when you feel able.

Once your treatment is over, gradually increase your activity. Try to balance rest periods with exercise such as walking. This will help build up your energy levels.

Bladder changes

Radiotherapy can irritate the bladder. You may feel like you need to pass urine more often. You may also have a burning feeling when you pass urine. Your doctor can prescribe medicines to make passing urine more comfortable.

Try drinking at least two litres (3½ pints) of water or other fluids each day to help with the symptoms.

Bowel changes

Radiotherapy to the pelvis may irritate your bowel and cause tummy (abdominal) cramps. If you have cramps tell your doctor, nurse or radiographer. They can give you medication to help.

Your bowels may open more often or you may have diarrhoea. Drink plenty of fluids if you have diarrhoea. Your doctor may prescribe medication to help manage it.

It may also help to eat a low-fibre diet during treatment and for a couple of weeks after it. This means avoiding:

  • wholemeal bread and pasta
  • raw fruit
  • cereals
  • vegetables.

Changes in your blood

External radiotherapy can reduce the number of blood cells made by your bone marrow. This is more likely to happen if you are having chemoradiation.

If your white blood cells are low, you are more prone to infection and may need antibiotics. If your red blood cell count is low, you may feel tired and you may need a blood transfusion. Your hospital team will arrange for you to have regular blood tests if needed.

Vaginal discharge

You may have a light vaginal discharge after treatment has finished. If it continues or becomes heavy, let your clinical oncologist or specialist nurse know.

Possible late effects of radiotherapy for vulva cancer

Radiotherapy to the pelvic area can sometimes cause problems months or years after treatment. These are called late effects. These may be permanent. If they happen, there are lots of ways to manage or treat them.

It is always important to tell your GP or cancer doctor about any new symptoms that develop, even if it is a long time after treatment. They need to be checked as they may not be caused by radiotherapy.

Early menopause

Radiotherapy to the pelvis affects the ovaries. This can stop the ovaries from working and cause you to have an early menopause. This means you will make less of the female hormone oestrogen and you will no longer have monthly periods. This can happen about 2 to 3 months after the treatment starts.

Symptoms of the menopause can include:

  • hot flushes and sweats
  • lower sex drive
  • mood swings and poor concentration
  • vaginal dryness

Your healthcare team will discuss this with you before your treatment starts. They can also give you information about treatments to manage menopausal symptoms, such as hormone replacement therapy (HRT).

Effects on the vagina

Radiotherapy can make your vagina narrower and less stretchy. The vaginal walls may be dry and thin, and can stick together. This can make penetrative sex and internal examinations uncomfortable.

Your hospital team may recommend you use vaginal dilators to help. Dilators are tampon-shaped plastic tubes of different sizes, which you use with a lubricant.

Although dilators are commonly used, there is no strong evidence about how effective they are. Rarely, they may cause damage to the vagina, especially if they are not used correctly. Your specialist nurse or doctor will explain the best way to use them.

Vaginal dryness can feel uncomfortable, particularly during sex. Creams, gels, lubricants or pessaries (small pellets that are put inside the vagina) can help.

There are lots of products you can try. You can buy them from chemists or online, or your doctor can prescribe them.

Moisturisers work by drawing moisture into the vaginal tissue. You apply them regularly. You can also use lubricants when you have sex to make it feel more comfortable and pleasurable. Lubricants can be water-based or oil-based. You can buy them from chemists, some supermarkets or online.

Vaginal dryness can make you more likely to get infections, such as thrush. Let your doctor know if you have symptoms such as itching or soreness.

Vaginal bleeding

After pelvic radiotherapy, the blood vessels in the lining of the vagina can become fragile. This means they can bleed more easily, especially after sex. Bleeding may also be caused by the vaginal tissue sticking together, or scar tissue causing the vagina to narrow.

If you have any bleeding, always let your cancer doctor or nurse know. They will examine you and explain whether it is likely to be caused by the radiotherapy. If the bleeding is minor, you may find that it does not trouble you much once you know the cause.

Changes to the vulva

The skin of the vulva may become permanently discoloured (reddened or darker). You may have some swelling in the vulva for months or sometimes years after radiotherapy. This can be reduced by gentle, upwards massage. A specialist nurse or physiotherapist can teach you to do this.

Bowel or bladder late effects

After radiotherapy, some women may develop changes to the bowel or bladder. It is common to have some mild changes. But it is much less common to have severe side effects that affect your quality of life. If this happens, symptoms may develop months or sometimes years after radiotherapy treatment.

If your bowel is affected, you may have to go the toilet more often or more urgently than usual, or you may have diarrhoea.

If the bladder is affected you may need to go to the toilet more often or more urgently.

The blood vessels in the bowel and bladder can become more fragile. This can cause blood in your urine or bowel movements. If you have bleeding always tell your cancer doctor or GP so that it can be checked.


Pelvic radiotherapy may increase the risk of swelling in one, or both, legs. This is called lymphoedema. It is not common but the risk is higher if you have surgery to remove the lymph nodes as well as radiotherapy. We have more information about how you can reduce the risk of lymphoedema.

Changes to the pelvic bones

Radiotherapy can cause thinning of the bone in the pelvis. This often does not have any symptoms but is seen on scans. In some women it may cause fractures in the pelvis called insufficiency fractures. These can cause pain in the lower back or pelvis. If this happens, it can be treated with painkillers and physiotherapy.