Vulval intraepithelial neoplasia (VIN) is a condition that can become cancer in some women. In other women, VIN will go away by itself. Treating VIN significantly reduces the cancer risk.

VIN is not a common problem. It usually starts in middle age, but can occur from young adulthood. It may be more common in people with light skin.

No-one is sure exactly what causes VIN, but it is more common in women who:

• smoke
• have human papillomavirus (HPV) infection (the same virus that is involved in cervical cancer)
• may have had genital herpes
• have a suppressed immune system
• have a skin condition called lichen sclerosis, which involves itching, pain and a change in the colour of affected parts of the vulva.

Symptoms of VIN

There may be no symptoms, but there is usually itching around the vulva, burning, and raised patches of skin that are a different colour to unaffected areas.

Women should take such symptoms seriously and not assume that all itching is thrush. VIN takes years to progress to cancer, if at all, but it does need to be diagnosed, monitored and treated if needed.

How VIN is diagnosed

If there is a suspicion of VIN, gynaecologists may use an instrument called a colposcope.

A colposcope looks like a pair of binoculars sitting on a large stand. It does not enter the body – the doctor inserts an instrument called a speculum into your vagina and then views a magnified picture of the vulva, cervix and vagina through the colposcope.

This procedure can help identify where abnormal or changed cells are located and what they look like. The doctor will probably take a tissue sample (biopsy) during the procedure.

Pathologists assess the seriousness of VIN in an individual woman from the biopsy. They look at the depth of the abnormal cells and how far they have spread.

Because VIN is similar to vaginal intraepithelial neoplasia (VAIN) and the precancerous changes that can occur on the cervix, some experts believe that a woman with VIN should be more closely screened for these other problems.

Treatment of VIN

Laser treatment or surgery may be used to remove the affected tissue.

If VIN is close to the clitoris, care will be taken in the choice and extent of treatment.

Some doctors use chemotherapy drugs formulated into creams, but these can cause a lot of inflammation and are not supported by all specialists.

Whatever treatment is given, careful follow-up is needed in case the VIN comes back.