Human papillomavirus (HPV) is a virus responsible for abnormal tissue growth and other cellular changes. It can be spread through skin contact during sexual activity. There are more than 100 different types or strains of HPV classified as "low-risk" (because they only cause warts) or "high-risk" (which means they can cause cancer). HPV is known to cause the most invasive cervical cancer in women, but not only women can be affected. It can cause cancer of the vulva and the vagina (in women), cancer of the penis (in men) and cancer of the anus, mouth, and throat in both sexes. HPV causes cancer after infecting cells in these regions. Over time, the infection can cause precancerous changes in cells, which may eventually lead to mutation to cancer cells. These events take several years.
What Types of Cancer Can Be Caused By HPV?
High-risk strains of HPV cause about 5% of all cancers worldwide, including those of:
• cervix • anus • head and neck • penis • Vagina and vulva • Oropharynx (throat)
There are several strains of high-risk HPV, but strains 16 and 18 are responsible for most cancers caused by HPV. In fact, these two strains cause 70% of all cervical cancers and can also cause most cancers of the oropharynx, vagina, vulva, and penis. Although cervical cancer is the most common cancer associated with HPV globally, there is an increasing rate of cancer of the oropharynx in recent times, especially in men.
How Does HPV Cause Cancers?
If high-risk HPV infects cells in the cervix, oropharynx, vulva, vagina, penis, or anus, it can cause cellular changes. These modified cells can become cancerous if the immune system does not eliminate them. Fortunately, most HPV infected cells are cleared off before they become precancerous. Only a persistent infection with a high-risk subtype increases the risk of cancer.
How To Reduce the Risk of HPV-Related Cancer
Although most people with HPV do not develop cancer, there are ways to reduce the risk of HPV. The first step to reducing the risk of developing HPV cancer is to avoid the risk of contracting HPV. This can be prevented and monitored by taking the appropriate vaccinations, practising safe sex, and having regular pap smear tests if sexually active.
Vaccines
Vaccines can offer prevention against HPV infections that can cause cancer. It is important to get vaccinated early before starting sexual activity. It is recommended that the HPV vaccine be administered for boys and girls 9 to 14 years of age, ideally 11 to 12 years of age. However, vaccines cannot prevent cervical cancer if the patient is already infected with the virus.
Safe Sex
You can reduce your risk of developing HPV infection by using a condom every time you have sex. You can still get HPV in areas exposed by the condom, so it is not considered a vaccine replacement. However, condoms can provide some protection against HPV and other sexually transmitted infections.
Pap Smear Test
There are unfortunately no approved HPV tests for men currently. However, pap smear tests are used for women. During a pap smear test, a doctor collects cells from the cervix to check for any abnormalities in the cervix that may indicate precancerous changes. Tests conducted on the cells from the cervix can also check for HPV.
For more information or questions about HPV and HPV infections that can put one at risk of cancer, please contact your GP or healthcare provider.