Vulvar cancer

What is vulvar cancer?

Vulvar cancer can start in any part of the external female sex organs (genitals). It most commonly develops in the labia majora, labia minora and the perineum. Less often, it involves the clitoris, mons pubis or Bartholin glands. There are several types of vulvar cancer. 

Learn more about:

• The parts of the vulva
• Types of vulvar cancer
• Who gets vulvar cancer?
• What causes vulvar cancer?

The vulva

The vulva is part of the female reproductive system, which also includes the ovaries, fallopian tubes, uterus, cervix and vagina.

The vulva is a general term for a woman’s external sexual organs (genitals). The main parts of the vulva are the:

• mons pubis – the soft, fatty mound of tissue covered with pubic hair, above the labia
• labia majora – two large, outer fleshy lips, which surround the inner lips known as labia minora
• labia minora – two inner lips (may be smaller or thinner than the labia majora)
• clitoris – the main organ for sexual pleasure in women. It is located where the labia minora join at the top of the vulva. During arousal, the clitoris fills with blood and becomes erect, and its stimulation can lead to sexual climax (orgasm)
• Bartholin glands – two small glands near the opening of the vagina.  They produce mucus to lubricate the vagina.

The vagina

Sometimes called the birth canal, the vagina is a muscular channel about 7–10 cm long that extends down from the cervix (neck of the uterus) to the vulva. The vaginal opening is where menstrual blood flows out of the body, sexual intercourse occurs, and a baby is born.

Urethra, anus and perineum

Below the clitoris is the urethra, for passing urine. Further down is the entrance to the vagina, and behind that is the anus. The area of skin between the vagina and the anus is called the perineum.

Female sexual anatomy

What are the types of vulvar cancer?

The types of vulvar cancer are named after the cells they start in:

Squamous cell carcinoma (SCC) 

The most common type, accounting for about 9 out of 10 (90%) cases. It starts in the thin, flat (squamous) cells lining the vulva. The two main subtypes are keratinising vulvar carcinomas (not linked to HPV) and warty/ basaloid (linked to HPV). Also includes verrucous carcinoma, a rare subtype, that looks like a large wart and grows slowly.

Vulvar (mucosal) melanoma  

Makes up about 2–4% of vulvar cancers. It starts in the cells that give the skin its colour (melanocytes), which are also found in the moist lining of the vulva. Mucosal melanomas are not related to overexposure to UV radiation.

Sarcoma

A rare type that starts in cells in muscle, fat and other tissue under the skin. It tends to grow faster than other types.

Adenocarcinoma

A rare type that develops from the mucus-producing (glandular) cells in the Bartholin glands or other vulvar glands. It includes extramammary Paget’s disease, which looks like eczema.

Basal cell carcinoma (BCC)

Although the most common form of skin cancer, BCC is a very rare type of vulvar cancer that starts in tall (basal) cells in the skin’s lower layer.

Who gets vulvar cancer?

Vulvar cancer is not common – each year in Australia, about 340 women are diagnosed with vulvar cancer. Although it most commonly affects women who have gone through menopause, diagnoses of vulvar cancer in women under 60 have increased in recent years. This is likely to be due to rising rates of infection with HPV.

What causes vulvar cancer?

The exact cause of vulvar cancer is unknown, but factors that increase the risk of developing it include:

Vulvar intraepithelial neoplasia (VIN)

This precancerous condition causes changes in the skin of the vulva. The vulva may itch, burn or feel sore. VIN may disappear on its own, but most women with VIN need some treatment. The condition sometimes becomes cancerous – about one in three women diagnosed with vulvar cancer also has VIN.

Human papillomavirus (HPV)

Also known as the wart virus, HPV is a sexually transmitted infection that can cause women to develop VIN. It can be many years between the initial infection with HPV and the first signs of VIN or vulvar cancer. HPV is a common virus and most women with HPV don’t develop vulvar or any other type of cancer. Although HPV is sexually transmitted, vulvar cancer itself is not contagious and it can’t be passed on to other people through sexual contact.

Abnormal cervical screening test

If a woman has had any abnormal cell changes detected on a cervical screening test, she has a slightly higher risk of developing vulvar cancer.

Other skin conditions

Vulvar lichen planus and vulvar lichen sclerosus are skin conditions that can cause itching and soreness. If not treated, these conditions can cause permanent scarring and narrow the vaginal opening. In a small number of women, they may develop into vulvar cancer after many years.

Other cancers

Women who have had cervical cancer or vaginal cancer have an increased risk of developing vulvar cancer.

Smoking

Cigarette smoking increases the risk of developing VIN and vulvar cancer. This may be because smoking can make the immune system work less effectively.

Weakened immune system

Women who’ve had an organ transplant or have human immunodeficiency virus (HIV) may be at higher risk of developing vulvar cancer because their immune system is not working normally.