Human Papilloma Virus (HPV)
Human papillomaviruses (HPV) are common viruses that can cause warts, which are benign (noncancerous) tumors. There are more than 100 types of HPV. Most are harmless and may cause warts on hands and feet, but about 30 types put you at risk for cancer. These types affect the genitals and you get them through sexual contact with an infected partner. They are classified as either low-risk or high-risk. Low-risk HPV can cause genital warts. High-risk HPV can lead to cancers of the cervix, vulva, vagina, and anus in women. In men, it can lead to cancers of the anus and penis.
Genital HPV infections are very common and are predominantly sexually transmitted; however, in some cases doctors cannot say for certain when infection occurred. In fact, HPV is spread through skin-to-skin contact, and thus, you can still contract HPV without vaginal or anal penetration. Most HPV infections occur without any symptoms and go away without any treatment over the course of a few years. However, HPV infection sometimes persists for many years, with or without causing cell abnormalities. This can increase a woman’s risk of developing cervical cancer.
Genital warts: Some types of HPV may cause warts to appear on or around the genitals or anus. Genital warts (technically known as condylomata acuminata) are most commonly associated with two HPV types, HPV–6 and HPV–11. Warts may appear within several weeks after sexual contact with a person who is infected with HPV, or they may take months or years to appear, or they may never appear. HPVs may also cause flat, abnormal growths in the genital area and on the cervix (the lower part of the uterus that extends into the vagina). However, HPV infections of the cervix usually do not cause any symptoms.
Connection between HPV and cancer
Some types of HPV are referred to as “low-risk” viruses because they rarely cause lesions that develop into cancer. HPV types that are more likely to lead to the development of cancer are referred to as “high-risk.” Both high-risk and low-risk types of HPV can cause the growth of abnormal cells, but only the high-risk types of HPV lead to cancer. Sexually transmitted, high-risk HPVs include types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, and 73. These high-risk types of HPV cause growths on the cervix that are usually flat and nearly invisible, as compared with the external warts caused by low-risk types HPV–6 and HPV–11. HPV types 16 and 18 together cause about 70 percent of cervical cancers. It is important to note, however, that the great majority of high-risk HPV infections go away on their own and do not cause cancer.
Persistent HPV infections are now recognized as the major cause of cervical cancer. Studies also suggest that HPVs may play a role in some cancers of the anus, vulva, vagina, and penile cancer (cancer of the penis). Additionally, studies have also found that oral HPV infection is a strong risk factor for developing cancer in middle part of the throat, the base of the tongue, and the tonsils.
What are the risk factors for HPV infection and cervical cancer?
Having many sexual partners is a risk factor for HPV infection. Although most HPV infections go away on their own without causing any type of abnormality, infection with high-risk HPV types increases the chance that mild abnormalities will develop and progress to more severe abnormalities or cervical cancer. However, even among the women who do develop abnormal cell changes with high-risk types of HPV, only a small percentage would develop cervical cancer if the abnormal cells were not removed. As a general rule, the more severe the abnormal cell change, the greater the risk of cancer. Studies suggest that whether a woman develops cervical cancer depends on a variety of factors acting together with high-risk HPVs. The factors that may increase the risk of cervical cancer in women with HPV infection include smoking and having many children.
The surest way to eliminate risk for genital HPV infection is to refrain from any genital contact with another individual.For those who choose to be sexually active, a long-term, mutually monogamous relationship with an uninfected partner is the strategy most likely to prevent genital HPV infection. However, it is difficult to determine whether a partner who has been sexually active in the past is currently infected.
HPV infection can occur in both male and female genital areas that are covered or protected by a latex condom, as well as in areas that are not covered. Although the degree of protection provided by condoms in preventing HPV infection is unknown, condom use has been associated with a lower rate of cervical cancer.
How are HPV infections detected?
A Pap test is the standard way to check for any cervical cell changes. A Pap test is usually done as part of a gynecologic exam. The U.S. Preventive Services Task Force guidelines recommend that women have a Pap test at least once every 3 years, beginning about 3 years after they begin to have sexual intercourse, but no later than age 21. During a Pap test, a HPV test (testing specifically for the presence of an HPV infection) can be performed, and if this test comes back indicating the need for further testing, such testing as a colposcopy and/or biopsy of any abnormal areas can be done. Colposcopy is a procedure in which a lighted magnifying instrument called a colposcope is used to examine the vagina and cervix. Biopsy is the removal of a small piece of tissue for diagnosis. Testing samples of cervical cells is an effective way to identify high-risk types of HPV that may be present. The HPV test can identify at least 13 of the high-risk types of HPV associated with the development of cervical cancer. This test, which looks for viral DNA, is performed by collecting cells from the cervix and then sending them to a laboratory for analysis. The test can detect high-risk types of HPV even before there are any conclusive visible changes to the cervical cells. There are currently no approved tests to detect HPV infection in men.
How is HPV treated?
Although there is currently no medical cure for human papillomavirus infection, the lesions and warts these viruses cause can be treated. Methods commonly used to treat lesions include cryosurgery (freezing that destroys tissue), LEEP (the removal of tissue using a hot wire loop), and conventional surgery. Similar treatments may be used for external genital warts. In addition, some drugs may be used to treat external genital warts. More information about treatment for genital warts can be found on the Centers for Disease Control and Prevention’s (CDC) Sexually Transmitted Diseases Treatment Guidelines Web page at http://www.cdc.gov/STD/treatment.
There are now vaccines (Gardasil® and Cervarix®) that can protect people against certain types of HPV. These vaccines are only used to prevent, not treat, an HPV infection. Gardasil® is highly effective in preventing infection with types 16 and 18, two “high-risk” HPVs that cause most (70 percent) cervical cancers, and types 6 and 11, which cause most (90 percent) genital warts. Cervarix was just approved for use in the United States by the FDA, while Gardasil has been approved for use in this country since 2006. In October 2009, the FDA also approved the use of Gardasil in males to prevent genital warts. Cervarix is approved for use in girls and young women ages 10 to 25 years, while Gardasil is approved for those 9 to 26 years old.
It is important to note that the vaccines help prevent these diseases, but do not treat them, and will not protect you against HPV types that you have already been exposed to. However, you may benefit from them even if you already have HPV, because you may not be infected with all types contained in the vaccines. However, talk to your health care professional on what would be the most appropriate course of action for you.
The vaccines now in use are given as a series of 3 shots over 6 months.The first one is given at a time that you and your health care professional decide will be appropriate. The second dose will be administered two months after the first one, and the third dose six months after the first dose.
To work best, the HPV vaccine should be given before a person starts having sex. The American Cancer Society recommends that the vaccine be given to females aged 11 to 12 (and as early as age 9 years if the doctor recommends it). The Society also recommends that "catch-up" vaccinations should be given to females up to age 18 who have not yet had the vaccine. Women age 19 to 26 should talk to their doctors about whether the vaccine is right for them. It is important to know that the vaccine doesn't protect against all cancer-causing types of HPV, so Pap tests are still needed.
Both types of the vaccine cost a lot — at least $375 (not counting the doctor's fee or the cost of giving the shots). While it should be covered by most medical insurance plans, you may want to check your coverage before getting the vaccine. In Cabell County, however, if you are uninsured or if your insurance does not cover the vaccine, you may be eligible to enroll in a program that will then pay for the costs of the vaccine. For more information regarding your specific case, please contact Cabell Huntington Health Department on phone (304) 526-3380.
(Information in the HPV section is taken from the American Cancer Society, www.cancer.gov)