Health A-Z

Medical Content Created by the Faculty of the
Harvard Medical School

Vaginal Cancer

What Is It?

Vaginal cancer is the uncontrolled growth of abnormal cells in the vagina, which is also called the birth canal.

Cancer that starts in the vagina is called primary vaginal cancer. Primary vaginal cancer is rare, accounting for only about 2% of cancers affecting the female reproductive system. It is more common that cancer cells found in the vagina came from cancer that started elsewhere, such as the cervix. There are two main types of primary vaginal cancer:

• Squamous cell carcinoma — Cancer cells grow from the surface layer of the vagina's lining. This cancer usually develops slowly. It commonly develops in the upper part of the vagina near the cervix. According to the National Cancer Institute, this type of cancer usually occurs in women between ages 50 and 70. According to the American Cancer Society, squamous cell carcinomas account for 85% to 90% of vaginal cancers.

• Adenocarcinomas — Cancer cells form in the glands in the vaginal wall. According to the American Cancer Society, this type of cancer is more often diagnosed in younger women. A subtype, called clear cell adenocarcinoma, is the most common. Daughters of mothers who took the drug diethylstilbestrol (DES) while pregnant have a higher risk of developing this rare form of cancer. DES, which was introduced in the 1940s to help prevent miscarriages, was banned from use in the United States in 1971. The American Cancer Society estimates that approximately 5% to 10% of vaginal cancers are adenocarcinomas. This is the most common type of vaginal cancer in women who are younger than 20 years old.

As with cervical and vulvar cancer, there is a newly recognized precancerous lesion known as vaginal intraepithelial neoplasia or VAIN. The significance of this lesion seems to parallel that of a similar lesion that arises in the cervix and vulva. It may predispose to the development of invasive cancer and is commonly associated with human papilloma virus infections.

Other, less common types of vaginal cancer include malignant melanomas and sarcomas. Melanoma tends to affect the lower or outer part of the vagina. Sarcomas develop deep in the vaginal wall.