There are several types of vulvar cancer, but some are extremely rare.

Squamous cell carcinoma

Most (9 out of 10) vulvar cancers develop from squamous cells, the skin cells of the vulva. These cancers usually grow very slowly over a few years.

There are several subtypes of squamous cell carcinomas:

• Keratising types are the most common, and are not linked to HPV infection.
• Basaloid and warty types are linked to HPV infection, but are less common.
• Verrucous carcinomas are rare, very slow-growing and look like a large wart.

Vulvar melanoma

Vulvar melanomas develop from melanin, the cells that produce pigment and give skin its colour. Melanomas are more common on sun-exposed skin, but they can start in other areas, such as the vulva. Only about 6 out of 100 vulvar cancers are melanoma.

Adenocarcinoma

Adenocarcinomas are very rare. They develop from cells that line the glands in the vulval skin – either in the Bartholin glands or in the sweat glands.

Paget’s disease of the vulva is when adenocarcinomas start in the top layer in the skin of the vulva.

Sarcoma

Sarcomas are extremely rare. Sarcomas develop from connective tissues of the body, such as muscle or fat under the skin, and tend to grow faster than other cancer types.

Basal cell carcinoma

Basal cell carcinomas are another type of cancer that are much more common on sun-exposed skin, but can rarely occur on the vulva. They start in the skin’s basal cells.

Precancerous vulvar skin changes

Vulvar intraepithelial neoplasia (VIN) is a pre-cancerous skin condition, which means that it can become cancer in some women. In some women, VIN will go away by itself, but treating VIN significantly reduces the risk of it developing into vulvar cancer.

There are 2 types of VIN:

• Usual-type VIN, which is more common in younger women and is caused by HPV infection.
• Differentiated-type VIN, which is more common in older women and is not linked to HPV.