Vaginal Cancer Causes and Risk Factors
Vaginal cancer is a relatively rare malignancy that originates in the vagina, a muscular canal that extends from the bottom of the uterus (cervix) to the vulva. Through this canal, the uterine lining is shed during menstruation, penetration can occur during sexual intercourse and a baby descends from the uterus during childbirth.
The most common type of vaginal cancer is squamous cell carcinoma, which forms in the flat squamous cells that line the vaginal walls. Less common types include:
- Adenocarcinoma - Forms in the vagina’s glandular cells
- Melanoma - Forms in the vagina’s pigment-producing skin cells (melanocytes)
- Sarcoma - Forms in the cells in the vagina’s muscular and connective tissues
What causes vaginal cancer?
Like all forms of cancer, vaginal cancer occurs when healthy cells undergo harmful changes that cause them to grow and multiply uncontrollably. All cells have DNA that instructs them to grow at a set rate and to self-destruct at the end of their life cycle. Cancer begins when a cell’s DNA is damaged to the point that its normal growth patterns are disrupted. As the abnormal cell replicates, it creates copies of itself. The excess abnormal cells then accumulate and form a tumor. If left untreated, the tumor may invade the surrounding structures, enter the bloodstream or lymphatic system and travel to distant organs and tissues.
The precise causes of the cellular DNA damage that leads to the development of vaginal cancer are not well understood. However, many women who are diagnosed with vaginal cancer also test positive for antibodies associated with certain high-risk strains of human papillomavirus (HPV) that have been linked to cervical cancer. Therefore, experts believe there is also a relationship between vaginal cancer and HPV, a common sexually transmitted infection.
Vaginal cancer risk factors
In addition to HPV, scientists have identified several factors that can increase the risk of vaginal cancer. Some of these risk factors, such as tobacco use and excessive alcohol consumption, are behavioral and can be controlled through healthy lifestyle choices. However, most vaginal cancer risk factors cannot be controlled, such as:
In general, cancer risk increases with age. The average age at the time of a vaginal cancer diagnosis is 60.
Exposure to diethylstilbestrol (DES) in utero
A synthetic form of the female hormone estrogen, DES was routinely prescribed to pregnant women in the United States between 1940 and 1971 to help prevent miscarriage. A woman may have been exposed to DES as a fetus if her mother took the drug while pregnant with her.
Primarily found in DES daughters, vaginal adenosis occurs when glandular tissue forms in the vaginal walls, where it is not normally found. Known as the epithelium, this tissue has a cylindrical shape and covers the mucous membranes in the vagina. Although vaginal adenosis is a benign condition, it can progress into cancer if left untreated.
Cervical cancer and precancer
Cervical cancer and precancerous conditions, such as cervical dysplasia, are known to increase the risk of vaginal squamous cell carcinoma. Many experts believe this is likely because cervical cancer and vaginal cancer share certain risk factors, such as HPV infection.
Human immunodeficiency virus (HIV)
Two of the most important risk factors for vaginal cancer are chronic HPV infection and cervical abnormalities. Because HIV weakens the body’s immune system, women with HIV are more likely to have a persistent HPV infection, which can also lead to cervical abnormalities and cancer.
Chronic vaginal irritation
Overly stretched pelvic ligaments may allow the uterus to sag into the vagina or extend outside of the vagina. Known as uterine prolapse, this condition can be treated with surgery or by wearing a device to hold the uterus in place (pessary). The use of a pessary can lead to long-term vaginal irritation, which slightly increases the risk of vaginal squamous cell carcinoma.
It is important to note that many women who have one or more risk factors never develop vaginal cancer, and some women who are diagnosed with vaginal cancer have no known risk factors. For individualized advice and guidance, women are encouraged to discuss their risk profile with a physician.
Vaginal cancer prevention
Although vaginal cancer cannot be completely prevented, a woman can take steps to reduce her risk. These include:
- Getting regular pelvic examinations and Pap tests
- Getting the HPV vaccine
- Not smoking
Benefit from world-class care at Moffitt Cancer Center
Moffitt offers a full slate of the latest techniques for detecting vaginal cancer in women who are at risk but do not have symptoms. In general, we recommend an annual pelvic exam for all women, as well as HPV testing for women 30 and older. The multispecialty team in our gynecological clinic helps many women achieve the best possible outcome and quality of life by detecting and addressing vaginal cancer early, when there are generally more treatment options available, including promising clinical trials.
Moffitt is also home to a full-time team of more than 800 researchers, all of whom share a commitment to broadening our understanding of how cancer develops and spreads—and most importantly, how it can be prevented and cured. Our research team leads groundbreaking discoveries on a regular basis, and then fast-tracks those discoveries into new diagnostic tools and treatments. In recognition of our notable contributions to cancer research, the National Cancer Institute has designated Moffitt a Comprehensive Cancer Center.
If you would like to learn more about vaginal cancer causes and risk factors, a specialist in our gynecological clinic can provide detailed information and create an individualized risk profile for you. To request an appointment, call 1-888-663-3488 or submit a new patient registration form online. No referral is necessary.