Definition of Cancer - vulva:

Vulvar cancer is cancer that starts in the vulva, the outside part of the female reproductive system that includes the labia and clitoris. The vulva opens into the vagina.

Causes, incidence, and risk factors:

Vulvar cancer most often affects the labia, the folds of skin outside the vagina. In some cases, vulvar cancer may start on the clitoris or in glands on the sides of the vagina opening.

Most vulvar cancers begin in skin cells called squamous cells. The others are classified as:

• Adenocarcinoma
• Basal cell carcinoma
• Melanoma
• Sarcoma

Vulvar cancer is relatively rare. The cause is unknown. A sexually-transmitted disease such as human papilloma virus (HPV, or genital warts) may play a role.

Cancer of the vulva usually occurs after menopause, typically in women age 50 or older. However, 15% of cases occur in women age 40 or younger.

Risk factors include:

• Diabetes
• High blood pressure
• History of cervical cancer or vaginal cancer
• HPV infection
• Syphilis infection
• Obesity

Women with a condition called vulvar intraepithelial neoplasia (VIN) have a greater risk of developing vulvar cancer that spreads. However, most cases of VIN never lead to cancer.