Vaginal cancer - Causes of vaginal cancer

The exact cause of vaginal cancer is unknown, but there are risk factors that increase your chances of getting it, including HPV, smoking and your age.

How does cancer begin?

Cancer begins with a change in the structure of DNA, which is found in all human cells. DNA provides cells with a basic set of instructions, such as when to grow and when to reproduce.

A change in the DNA's structure (genetic mutation) alters these instructions so that the cells carry on growing and reproducing uncontrollably. This produces a lump of tissue (a tumour).

How does cancer spread?

Left untreated, cancer can quickly grow and spread to other parts of your body, such as your bones and organs. The cancer can be spread through either the bloodstream or lymphatic system.

The lymphatic system is a network of channels and glands called lymph nodes, which are distributed throughout your body. They remove unwanted bacteria from your body and are part of your immune system (the body's defence system).

Increased risk

Evidence suggests that certain risk factors can increase your likelihood of developing vaginal cancer.

Human papilloma virus (HPV)

Human papilloma virus (HPV) is the name given to a family of viruses that affect the skin and the moist membranes that line the body, such as those in the cervix, anus, mouth and throat. HPV is spread during sexual intercourse, including anal and oral sex.

There are many different types of HPV and up to 8 out of 10 people are infected with the virus at some time during their lives. In most cases the virus does not cause any harm and you will not go on to develop vaginal cancer.

However, HPV is present in more than two-thirds of women with vaginal cancer, which suggests that HPV may increase your risk of developing vaginal cancer. 

HPV is known to cause changes in the cells of the cervix, which can lead to cervical cancer. It is thought that the virus could have a similar effect on the cells of the vagina.

HPV-16 is the type of HPV most strongly linked to vaginal cancer. The HPV vaccination, which is offered to girls aged 12 to 13, protects against this type of HPV.

Read more about the HPV vaccination.

Diethylstilbestrol

The medicine diethylstilbestrol is another known risk factor for vaginal cancer. It can cause a type of vaginal cancer called clear cell adenocarcinoma.

Diethylstilbestrol was widely prescribed for pregnant women between 1938 and 1971. At the time, it was thought (wrongly) that the drug could help reduce the risk of miscarriage.

In 1971, researchers discovered a link between diethylstilbestrol and cancer in the children of women given the medicine. The use of diethylstilbestrol in pregnant women was therefore banned.

The risk of vaginal cancer associated with using diethylstilbestrol is small. As it is now around 40 years since the drug was banned, clear cell adenocarcinoma is very rare.

Other possible risk factors

Other possible risk factors for vaginal cancer include:

• a previous history of cervical intraepithelial neoplasia (CIN) – non-cancerous cells that can sometimes become cancerous
• a history of reproductive cancers, such as cervical cancer or vulval cancer 
• your age – 7 out of 10 cases of vaginal cancer occur in women who are over 60
• smoking
• HIV