There are three viruses known to cause cancer, one of them is HPV or Human Papillomavirus. While this virus has been in the news lately, it has actually been around for several hundred years.
HPV is typically referred to as an STI (sexually transmitted infection) because it is transferred, for the most part, during sexual activities. I say activities because it does not require actual intercourse to spread the virus but merely skin-to-skin contact predominantly with mucous membranes such as occur in the vagina, mouth and anus.
HPV has an incubation period of approximately three months after which, symptoms may appear. However, this is often called the symptomless disease because, more often than not, it produces no symptoms at all. The body’s immune system can then suppress the virus and it can remain dormant in the body for weeks, months and even years. Because of this, it can return again later in life for a multitude of reasons not fully understood.
Some of these may include a decrease in the person’s immune system or an increase in viral load, the amount of the virus the body is exposed to. Reducing the viral load is one reasons why wearing condoms, even if in a monogamous relationship, remains important.
The human papillomavirus has what are referred to as high and low risk strains. A strain refers to the same virus with a slight difference. There are more than 150 strains of HPV documented to date. Some of these low risk strains cause such things as the warts found the hands and plantar warts on the feet. Other low risk strains cause genital warts.
High risk strains of HPV, thirteen of which are regularly tested for, can, if persistent, result in dysplasia or a changing within the normal cells. Dysplasia can occur in varying degrees basically low, intermediate and high risk for causing cancer.
Dr. Ralph Richart, M.D., and pathologist at Columbia Presbyterian Medical Center in New York City developed the term intraepithelial neoplasia (IN) meaning an abnormal change within the epithelial layers of the skin. The letter symbolizing the part of the body affected comes before such as CIN for cervical intraepithelial neoplasia and so on. This is further broken down into CIN1, CIN2 and CIN3/CIS (carcinoma in situ).
Up to sixty percent of CIN2 lesions can regress themselves however, there are still forty percent which may not. The current recommendations by the ASCCP (American Society of Colposcopy and Cervical Pathology) still calls for treatment of CIN2 lesions or greater in order to reduce the number of potential cancers.
The majority of CIN3 lesions, if untreated, will go on to result in cancer. The numbers utilized basically explain the degree of tissue which is affected with abnormal cells. Simply put, CIN1 affects one-third, CIN2 two-thirds and so on.
While there is no cure for HPV, there is treatment for the various conditions it can cause if caught early. There is also a vaccine which protects against two low risk(those that cause ninety percent of genital warts) and two high risk strains of HPV (those that cause ninety-nine percent of cervical cancers and over eighty percent of anal cancers).
Routine screening via Pap smear and also anal Pap by a colorectal surgeon or other physician can result in early detection of these strains allowing the patient to receive the more scrupulous follow-up that he or she requires.
Ask your physician about the HPV vaccine, as well as the anal pap, which has been slow to gain acceptance amongst the medical community as a whole. Patient advocacy can help to chance this going forward, and when it comes to cancer, the majority of types diagnosed early maintain a much better prognosis.
Resources:
http://www.thecmafoundation.org/projects/HPV/ProviderResources_CME.aspx
http://dceg.cancer.gov/about/staff-bios/kreimer-aimee
http://www.cdc.gov/std/hpv/HPVWebcast.pdf
http://www.sciencedirect.com/science/article/pii/S1043148905000126
http://www.iuhpe.org/uploaded/Activities/Scientific_Affairs/CDC/CCPP%20Training%20Module%20-%20Epi%20and%20Natural%20History%20of%20CaCx.pdf
http://www.iuhpe.org/uploaded/Activities/Scientific_Affairs/CDC/CCPP%20Training%20Module%20-%20Epi%20and%20Natural%20History%20of%20CaCx.pdf
http://www.traveldoctoronline.net/epidemiology-of-human-papillomavirus-infection-in-men--cancers-other-than-cervical-and-benign-conditions-MTg4NDc1NTQ=.htm
Histology, classification and natural history of cervical intraepithelial neoplasia (CIN) www.cme.hu/dlObject.php?aid=523&/...pdf Chap 42 page 7.
Reviewed July 25, 2011
by Michele Blacksberg R.N.
Edited by Shannon Koehle