The female external genitals, also called the vulva, consist of the labia majora and labia minora, the vaginal vestibule and the clitoris. The labia majora are flaps of skin covered with pubic hair that surround the pubic cleft. Between them lie the labia minora, which are thin, hairless, wrinkled skin folds that appear darker due to their strong pigmentation. Depending on their length, the labia minora either lie hidden in the pubic cleft or protrude from it. The labia surround the vaginal vestibule and protect the vagina and urethra from knocks and foreign bodies. The clitoris lies between the labia majora and labia minora, surrounded by a fold of skin. The clitoris generates sexual pleasure and has no other known functions.
Vulvar cancer is a rare type of tumour that only affects about 7 or 8 women out of 100,000 per year.
The exact causes of the development of vulvar cancer are largely unknown. Risk factors for vulvar cancer include other sexually transmitted infections, for example herpes viruses, chlamydia and syphilis, but these alone cannot cause vulvar cancer. Smoking, some chronic diseases of the vulva and vagina, or a reduction in immune functioning due to HIV or medication also increase the risk of developing vulvar cancer. Another risk factor is cancer or precancerous lesions in the genital and anal area. Chronic inflammatory skin diseases, such as lichen sclerosus, are also regarded as an important risk factor for keratinized squamous cell carcinomas of the vulva.