Vulval intraepithelial neoplasia (VIN)

VIN is divided into two main types.

Certain factors can increase your chance of developing VIN. Having one or more risk factor below does not mean you will get VIN. But not having any risk factors does not mean you will not get VIN.

The main cause of HSIL is an infection called the human papilloma virus (HPV). There are different types of HPV. The types that cause abnormal cell changes in the vulva are called high-risk HPV.

Usually the body’s immune system gets rid of the virus naturally. There are no symptoms and often the virus does not cause damage. Most people will never know they had it.

In some people, the immune system does not clear the infection and the virus stays in the body for longer. If the vulva is affected by HPV, it means the virus may cause damage that over a long time can develop into HSIL.

HPV is very common and most people have it at some point. The virus can live on the skin around the whole genital area. It passes easily from person to person during any type of sexual contact. This includes skin-to-skin genital contact or using sex toys.

This means that using a condom or other barrier contraception may reduce your risk of HPV infection, but it does not offer complete protection.

Your risk of developing HSIL is much higher if you smoke. This may be because:

• smoking makes your immune system less effective at clearing HPV
• the chemicals in tobacco can damage your cells.

Your immune system helps protect your body from infection and illness. A weak immune system is less likely to get rid of infections like HPV. You may have a higher risk of HSIL if your immune system is weakened over the long term, for example by:

• smoking
• some conditions, such as HIV
• medicines used to suppress your immune system after an organ transplant.

If you are worried that you have a weakened immune system, talk to your GP or specialist nurse. They will be able to give you further advice.

The main risk factor for dVIN is having another vulval condition such as vulval lichen sclerosus (VLS) or lichen planus (VLP).

There are different types of treatment that can be used for VIN. The best treatment for you may depend on:

• the part of the vulva affected by VIN
• how many areas of VIN there are
• if you have any symptoms
• how likely it is that the VIN will develop into cancer (for example, the risk is higher if you have dVIN and vulval lichen sclerosus, or if you have a condition that weakens your immune system)
• your personal preferences.

If you have a small area of VIN or you have no symptoms, you may not need treatment. Your doctor may ask you to have regular check-ups to look for any changes.

Sometimes, it may be possible to delay treatment. For example, you may delay treatment if you are pregnant. Your doctor will give you more information about the risks and benefits of this.

If you do need treatment, your doctor will explain your options and you will decide together. The aim is to improve any symptoms you have and reduce your risk of vulval cancer.

The main treatment for VIN is usually a small operation to remove the affected area from the vulva. This is called a wide local excision.

Rarely, if the area is large or there are several areas, the whole vulva may be removed. This is called a vulvectomy. It is usually only considered when other treatments have not been successful or symptoms are difficult to manage.

We have more about both these types of surgery in our information about surgery for vulval cancer.

Ablation treatments destroy the area of VIN. This treatment may be used when it is difficult to remove the VIN with surgery. For example, if the VIN is around the clitoris. Ablation can be done using:

• a high-energy beam (laser)
• a tiny electrical current passed through a probe (diathermy).

The laser beam or diathermy is set on the affected areas to destroy the abnormal cells.

Your doctor will tell you about your treatment. They will explain how much skin is going to be removed or treated, and how this will affect you afterwards.

Imiquimod is a cream that uses your body’s immune system to get rid of VIN. You spread the cream on the areas of VIN. The treatment is usually for several months. You may need regular check-ups during this time.

Imiquimod can cause vulval inflammation and discomfort. This treatment may not be effective if you have a condition that weakens your immune system.

This treatment is not usually suitable for VIN differentiated type (dVIN). dVIN is usually removed rather than treated with cream as there is a higher risk of developing into vulval cancer.

Other treatments are sometimes used to treat VIN. Your doctor will explain if they may be suitable for you. Some treatments may only be available as part of a clinical trial.

Cidofovir

Cidofovir is a gel that you apply to the areas of VIN. Side effects include:

• vulval inflammation
• vulval discomfort
• tiredness.

Photodynamic therapy (PDT)

This treatment uses laser light to activate a light-sensitive drug. The drug can be a cream applied to the vulva, or an injection into a vein (intravenously). The doctor will shine a laser light onto the affected area. This activates the drug to destroy the abnormal cells.

VIN can come back after treatment, so you will see your specialist regularly, often for many years. They will check for signs of any further changes that may need treated.

If your risk of VIN returning is low, your specialist may discharge you into the care of your GP. If you notice any new symptoms or changes, it is important to let your GP know. They can organise for you to see your hospital specialist

If you smoke, giving up reduces the chance of the VIN coming back again. The NHS has a lot of information and support to help you give up smoking. If you want to stop smoking:

• in England, contact NHS Smokefree
• in Scotland, contact Stop Smoking
• in Wales, contact Help Me Quit
• in Northern Ireland, contact Stop Smoking.

It can be difficult to know who to talk to or how to start a conversation about living with a vulval condition. But for many people, talking about it is an important way of coping.

You may find it helpful to talk to family or friends. Or you may prefer help from someone you are not close to, such as a counsellor. There is no right or wrong way to cope, but help is available if you need it. You may find the following organisations helpful:

• Vulval Pain Society – information for people affected by conditions that cause vulval pain.
• The British Society for the Study of Vulval Disease – patient information and useful links to information about vulval conditions.

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

• Call the Macmillan Support Line on 0808 808 00 00.
• Chat to our specialists online