Causes and risk factors of vulval cancer

There are some possible risk factors for vulval cancer. If you have one or more it does not mean you will get cancer. Some people do not have any risk factors but still get cancer.

Risk factors of vulval cancer

The exact cause of vulval cancer is unknown. However, some risk factors can increase the chances of developing it.

Having one or more risk factors does not mean you will definitely get cancer. And if you do not have any risk factors, it does not mean you will not get vulval cancer.

If you are worried about vulval cancer and would like to talk to someone, we're here. You can:

Age

The risk of developing vulval cancer increases with age. Most people who are diagnosed with vulval cancer are aged 65 or over.

Vulval cancer in older people is usually linked to a skin condition called lichen sclerosus (LS).

Vulval cancer in younger people is often linked to human papillomavirus infection (HPV) and smoking.

HPV

The main risk factor for vulval cancer is an infection called human papilloma virus (HPV). There are over 100 types of this virus. Some can affect the vulva and cause abnormal cell changes that may develop into vulval cancer.

HPV is common and most people are infected with it at some point. It can be passed on through any type of sexual contact. It is often shared between sexual partners. Using a condom or other barrier contraception may reduce the risk of infection with HPV, but it does not offer complete protection.

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. We do not know exactly why this is. If the virus affects the vulva for longer, it can start to cause damage that may eventually cause cancer.

Vulval cancer itself is not infectious. You cannot catch cancer or pass it on to other people.

The NHS offers a vaccine to people between the ages of 11 and 13 to prevent HPV.

A week immune system

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. Your immune system can be weakened by:

  • smoking
  • some medical 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, if you have one. They will be able to give you further advice.

Vulval skin conditions

Some skin conditions of the vulva can increase the risk of developing vulval cancer.

Lichen sclerosus (LS) and lichen planus (LP)

These are common, non-cancerous skin conditions. They can affect different parts of the body, but commonly affect the vulva. When they affect the skin of the vulva, they are known as vulval LS or vulval LP.

Less than 5 in every 100 women (5%) who have vulval LS or LP develop vulval cancer. Over a long period of time, the inflammation caused by these skin conditions may increase the risk of cancer developing.

Paget's disease of the vulva

This condition causes abnormal changes in the cells that cover the skin of the vulva. It is rare and usually only affects people who have been through the menopause. In a small number of cases, cancer is found underneath the area where the Paget’s disease is.

Vulval intraepithelial neoplasia (VIN)

The term VIN describes changes that happen in the skin that covers the vulva. If the changes become more severe, there is a chance cancer might develop after many years. VIN is called a pre-cancerous condition.

VIN is divided into two main types:

  • HSIL – High-grade squamous intraepithelial lesion of the vulva. This is more common. It is usually linked to a virus called HPV. This type was previously called VIN usual type (uVIN).
  • dVIN – VIN differentiated type. This is rarer. It often occurs together with other skin conditions that can affect the vulva, such as lichen sclerosus (LS) or lichen planus (LP). It is not usually linked to the HPV virus.

Smoking

Smoking increases the risk of developing both VIN and vulval cancer. Smoking makes the immune system less effective and less able to get rid of HPV. This may be one of the reasons it increases the risk of vulval cancer.

CIN

High grade abnormal cell changes in the cervix (called (CIN 3) may increase the risk of developing vulval cancer. This may be related to shared risk factors, such as HPV infection and smoking.

About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Senior Medical Editor, Professor Nick Reed, Consultant Clinical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We try to make sure our information is as clear as possible. We use plain English, avoid jargon, explain any medical words, use illustrations to explain text, and make sure important points are highlighted clearly.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected. Our aims are for our information to be as clear and relevant as possible for everyone.

You can read more about how we produce our information here.