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.

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.

• Local itching, pain, burning, bleeding
• Pain with intercourse
• Pain with urination
• Ulcer, thickening or lump
  • Usually on the labia majora
  • May be anywhere on the vulva
• Unusual odor

Nearly 20% of women with vulvar cancer have no symptoms.

The following are used to diagnose vulvar cancer:

• Biopsy
• Pelvic examination to look for any skin changes

Treatment involves surgery to remove the cancer cells. If the tumor is large (more than 2 cm) or has grown deeply into the skin, the lymph nodes in the groin area may also be removed.

Radiation, with or without chemotherapy, may be used to treat advanced tumors or vulvar cancer that comes back.

You can ease the stress of illness by joining a support group whose members share common experiences and problems. See cancer - support group.

Most women with vulvar cancer who are diagnosed and treated at an early stage do well. However, a woman's outcome depends on the size of the tumor, the specific type of vulvar cancer, and whether the cancer has spread. The cancer commonly comes back at or near the site of the original tumor.

Complications may include:

• Spread of the cancer to other areas of the body
• Side effects of radiation, surgery, or chemotherapy

Call your health care provider if you have any of these symptoms for more than 2 weeks:

• Local irritation
• Skin color change
• Sore on the vulva

Practicing safe sex may decrease your risk of vulvar cancer. This includes using condoms to protect against sexually transmitted diseases.

A new vaccine is available to protect against certain forms of HPV infection. The vaccine is approved to prevent cervical cancer and pre-cancers. It may help prevent other cancers linked to HPV, such as vulvar cancer. The vaccine is given to young girls before they become sexually active, and to adolescents and women up to age 26.

Routine pelvic exams can help diagnose vulvar and other cancers at an earlier stage. Earlier diagnosis improves the odds of treatment success.

American Cancer Society. Cancer Facts and Figures 2006. Atlanta, Ga: American Cancer Society; 2006.

Whitcomb BP. Gynecologic malignancies. Surg Clin North Am. 2008;88:301-317.