The vulva is the area of skin between a woman’s legs and is made up of all the visible sex organs. It consists of two outer lips (the labia majora), which are covered in pubic hair and surround two inner lips (the labia minora).
At the front of the vulva is a small structure (the clitoris) that helps women reach a sexual climax (orgasm). Just behind the clitoris is the outlet for urine (the urethra), and just behind this is the vaginal opening (birth canal). Further back still is the opening to the back passage (anus). This is close to the vulva, but not part of it. The area of skin between the vulva and the anus is called the perineum. All of these structures are visible from outside the body.
In the groin, where the skin creases at the top of each leg, there are lymph nodes. These are part of the lymphatic system. This system is an important part of the body’s natural defense against disease. The lymph nodes can become swollen if they are affected by an infection or cancer.
Types of vulval cancer
Cancer of the vulva is rare. It’s most likely to occur in women over the age of 60, but the number of younger women who are affected is increasing.
Vulval cancer can occur on any part of the external female sex organs. The inner edges of the labia majora and the labia minora are the most common areas for it to develop. Less often, vulval cancer may also involve the clitoris and the Bartholin glands. The Bartholin glands produce mucus that lubricates the vagina. They are small glands that are located on each side of the vagina. Vulval cancer can also sometimes affect the perineum.
Squamous cell carcinoma
9 out of 10 vulval cancers (90%) develop in the skin of the vulva from cells called squamous cells. This type of vulval cancer usually takes many years to develop. It usually starts with pre-cancerous changes to vulval cells, which slowly develop over several years into cancerous cells.
Melanomas develop from the pigment-producing cells that give the skin its color. Vulval melanoma is the second most common type of vulval cancer, but it’s much less common than the squamous cell type. Only about 4 out of every 100 vulval cancers (4%) are melanoma. Vulval melanoma usually looks like a dark patch on the vulva.
Verrucous carcinoma is a rare, very slow-growing type of squamous cell carcinoma that looks like a large wart.
These are very rare. Adenocarcinoma of the vulva develops from cells that line the glands in the vulval skin.
Basal cell carcinoma
This type of cancer very rarely affects the vulva. It develops from cells called basal cells that are found in the deepest layer of the skin of the vulva. It’s generally slow-growing and almost never spreads from the vulva.
Sarcomas of the vulva are extremely rare. Sarcomas develop from cells in tissue such as muscle or fat under the skin. They tend to grow more quickly than other types of vulval cancer.