Vaginal cancer

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

The vulva

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 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. 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.

Urethra, anus and perineum

Beneath the clitoris is the urethra, for passing urine. Further back is the entrance to the vagina, and below that is the anus. The area of skin between the vagina and the anus is called the perineum.

Vaginal cancer is one of the rarest types of cancer affecting the female reproductive system (gynaecological cancer). Each year in Australia, about 70 women are diagnosed with vaginal cancer, and the average age at diagnosis is 70. However, vaginal cancer, particularly adenocarcinoma, can sometimes occur in younger women.

Squamous cell carcinoma (SCC)

• starts in thin, flat (squamous) cells that line the vagina
• most likely to occur in the upper vagina
• usually grows slowly over many years
• makes up about 85% of vaginal cancers.

Adenocarcinoma

• develops from the mucus-producing (glandular)
  cells of the vagina
• more likely to spread to the lungs and lymph nodes
• makes up 5–10% of vaginal cancers
• includes clear cell carcinoma.

Vaginal melanoma

• a type of skin cancer that develops from the cells
  that give the skin its colour (melanocytes)
• a rare form of vaginal cancer.

Sarcoma

• develops from muscle, fat and other tissue deep
  in the wall of the vagina
• a rare form of vaginal cancer.

Secondary cancer in the vagina is more common than primary vaginal cancer. This means the cancer has spread from another part of the body, such as the cervix, uterus, vulva, bladder, bowel or other nearby organs.

Secondary vaginal cancer is managed differently to primary vaginal cancer. For more information, speak to your treatment team. 

The exact cause of vaginal cancer is unknown. Vaginal cancer is not contagious and it can’t be passed to other people through sexual contact. It is not caused by an inherited faulty gene and can’t be passed on to your children. 

Factors known to increase the risk include:

• Vaginal intraepithelial neoplasia (VAIN) – This is a precancerous condition that often has no symptoms. It means that the cells in the lining of the vagina are abnormal and may develop into cancer after many years. However, most women with VAIN do not develop vaginal cancer.
• Human papillomavirus (HPV) – Also known as the wart virus, HPV is a sexually transmitted infection that can cause women to develop VAIN. It can be many years between the initial infection with HPV and the first signs of VAIN or vaginal cancer. HPV is a very common virus and most women with HPV don’t develop vaginal or any other type of cancer.
• Smoking – Cigarette smoking doubles the risk of developing vaginal cancer. This may be because smoking can make the immune system work less effectively.
• Radiation therapy to the pelvis – If you have had radiation therapy to the pelvis for another reason, you are at a slightly higher risk of vaginal cancer. This complication is very rare.
• History of gynaecological cancer – Vaginal cancer is more likely to be diagnosed in women who have had cervical cancer or early cervical cell changes that were considered to be precancerous.
• Diethylstilboestrol (DES) – This synthetic hormone drug has been identified as a cause of a type of vaginal adenocarcinoma called clear cell carcinoma. Between 1938 and 1971 – and occasionally beyond – DES was prescribed to pregnant women to prevent miscarriages. It is no longer prescribed to pregnant women in Australia.

  The female children of women who took DES (called DES daughters) have an increased risk of developing a range of health problems. About one in 1000 DES daughters develops clear cell carcinoma of the vagina or cervix. If you are concerned about this risk, see your GP.