What Is Vulvar Cancer?

Cancer of the vulva or vulvar cancer, most often affects the inner edges of the labia majora or the labia minora. It starts in the clitoris or in the Bartholin glands less often.

Types of vulvar cancer

Vulvar cancer is named based on where it starts. The most common type of vulvar cancer is squamous cell carcinoma. Other less common types include basal cell carcinoma, melanoma, sarcoma, Paget disease of the vulva, and Bartholin gland carcinoma.   

Squamous cell carcinomas

Most cancers of the vulva are squamous cell carcinomas. This type of cancer starts in squamous cells, the main type of skin cells.  Squamous cancer can develop from a pre-cancerous condition, called vulva intraepithelial neoplasia (VIN). These changes in cells might, but do not always, become cancer.  

Types of squamous cell carcinoma

• The keratinizing type (the tumor cells make keratin, a protein) is most common. It usually develops in older women and is not linked to infection with human papillomavirus (HPV).  HPV is discussed in Risk Factors for Vulvar Cancer.
• Bowenoid and warty types are less common. These are the kinds more often found in younger women with HPV infections, most commonly HPV 16, 18, and 33.
• Verrucous carcinoma is  slow-growing and tends to have a good prognosis (outlook). This cancer looks like a large wart and a biopsy is needed to be sure it's not a benign (non-cancer) growth.

Basal cell carcinoma

This most common type of skin cancer, more often found on sun-exposed areas of the skin,  occurs very rarely on the vulva. Less than 8 of every 100 vulvar cancers are basal cell carcinomas.  For more information on this type of cancer, see Basal and Squamous Cell Skin Cancer.

Melanoma

Melanomas are cancers that start in the pigment-producing cells that give skin color. They are much more common on sun-exposed areas of the skin, but can start in other areas, such as the vulva. Vulvar melanomas are rare, making up about 6 of every 100 vulvar cancers.

More information on this can be found in Melanoma Skin Cancer.

Sarcoma

A sarcoma is a cancer that starts in the cells of bones, muscles, or connective tissue. Less than 2 of every 100 vulvar cancers are sarcomas. Unlike other cancers of the vulva, vulvar sarcomas can develop at any age, including in childhood.

Bartholin gland carcinoma

A cancer that begins in the Bartholin gland (a gland found inside the opening of the vagina) is called a Bartholin gland cancer. About 1 in every 1000 vulvar cancers are Bartholin gland cancers, which occur more commonly in older women. While most are adenocarcinomas or squamous cell carcinoma, a Bartholin gland cancer can also be an adenosquamous or adenoid cystic carcinoma. It can also be easily mistaken for a cyst (build-up of fluid in the gland), so it's common for it to take a while to get an accurate diagnosis.

Paget disease of the vulva

In Paget disease of vulva, also known as extramammary Paget disease (EMPD),  adenocarcinoma cells are found in the top layer of the vulvar skin, called the epidermis. The affected area of skin is usually itchy and red with raised edges.  In most cases, the adenocarcinoma cells have not moved past the epidermis.  However, up to 25% of patients with Paget's disease of the vulva also have an invasive vulvar adenocarcinoma, where the adenocarcinoma cells have moved past the epidermis to other structures (for example, the Bartholin gland). Since Paget disease of the vulva is commonly associated with other adenocarcinomas, patients with this diagnosis are usually checked for cancers in other organs, such as the breast, bladder, urethra, cervix, rectum, or ovary.