Risks and causes of vaginal cancer

• A quick guide to what's on this page
• What a risk factor is
• How common vaginal cancer is
• Age
• Changes in the cells lining the vagina
• Human papilloma virus infection

• HIV infection
• CIN or cancer of the cervix
• Smoking
• A drug called diethylstilbestrol
• Washing before and after intercourse
• Family history

Anything that increases your risk of getting a disease is called a risk factor. Different cancers have different risk factors. Even if you have one or more risk factors, it does not mean that you will definitely get that disease.

We don’t know the exact causes of vaginal cancer. It is a rare cancer - only about 250 new cases are diagnosed in the UK each year. That is only 1 out of every 1,000 cancers diagnosed in women.

Cancer starting in another place in the body such as cancer of the cervix, womb cancer or bowel cancer can spread to the vagina. This is not the same as cancer starting in the vagina. Cancer starting in the vagina is known as primary vaginal cancer. Cancer that has spread from another place in the body is called secondary cancer.

Because vaginal cancer is such a rare type of cancer, it is very difficult to carry out research involving large enough numbers to give any reliable results. But researchers have managed to identify several risk factors.

Cancer of the vagina mainly affects women over the age of 60. More than 7 out of every 10 cases (70%) occur in women over 60. It is an extremely rare type of cancer in women less than 40, except for a particular type of vaginal cancer called clear cell adenocarcinoma. This occurs in the daughters of women who took a drug called diethylstilboestrol during pregnancy.

A condition called VAIN can mean you are more at risk of getting vaginal cancer. VAIN stands for vaginal intraepithelial neoplasia. It means there are changes to the cells in the skin lining the vagina. These changes are not enough to make the cells cancerous. But they could become cancerous if not treated. There is more about vaginal intraepithelial neoplasia (VAIN) in this section of CancerHelp UK.

HPV is a common infection and is passed from one person to another by sexual contact. Around 8 out of 10 people (80%) in the UK will be infected with the HPV virus at some time during their lifetime. For most people the virus causes no harm and goes away without treatment. It is only when the infection won't clear up that sometimes there is a problem. But most women infected with HPV don’t go on to develop vaginal cancer.

HPV is present in more than half of the women who have vaginal cancer (50%) and more than 8 out of 10 women who have precancerous changes in the vagina (VAIN). There are many different types of human papilloma virus (HPV). HPV types 6 and 11 can infect the female and male genital organs and the anal area, causing visible genital warts. Women with these types of the virus are not likely to develop vulval cancer but some women do.

Women with HPV types 16, 18 and 31, as well as some others have a higher risk of developing genital and anal cancers. These types of HPV can cause changes in the cells covering the vagina. The changes make the cells more likely to become cancerous in time. But this can take years. Most women infected with these viruses do not develop cancer of the vagina. So other factors must also be needed. The type of HPV most strongly linked to vaginal cancer is HPV 16.

Although not designed to do so, having regular smear tests will help pick up vaginal cancer in its very early stages or in its precancerous stage (VAIN).

Women with HIV or AIDS have an increased risk of vaginal cancers, as well as other cancers in the genital or anal area. This may be because the body is less able to fight off HPV infection.

If you have had cervical cancer or pre-cancerous changes in your cervical cells, you have an increased risk of developing the most common type of vaginal cancer (squamous cell cancer). Precancerous cell changes are also called cervical dysplasia or CIN (which stands for cervical intraepithelial neoplasia).

There may be a link between cancer of the vagina and smoking. But there have only been a small number of studies looking into this and most studies show no increase in risk amongst smokers.

This drug used to be called diethylstilboestrol or DES. It is a drug that doctors sometimes gave to pregnant women in the past, to stop them having a miscarriage. The daughters of women who took DES during their pregnancy are more at risk of getting a type of vaginal cancer called clear cell adenocarcinoma.

DES was only used between 1945 and 1970 and researchers are still gathering information about its effects. It seems daughters of DES users are most likely to develop vaginal cancer between the ages 15 and 22. The oldest woman so far to get this type of cancer was 42 years old and the youngest girl was 7.

This is a very rare type of cancer and only 1 in 1,000 women with a mother who took DES will go on to develop it. Researchers are investigating other factors that may increase risk and might help to explain why only 1 in 1,000 women are affected. DES hasn't been used for over 35 years now, so it is becoming less important as a risk factor.

One study has suggested that washing the genital area before and after intercourse may reduce the risk of vaginal cancer. But more studies are needed to confirm this.

One study has shown an increased risk of vaginal cancer in women who have a sister diagnosed with cervical cancer.