Human Papilloma Virus (HPV) First Causes Infection
There are approximately 15 different types of human papillomavirus (HPV) that are sexually transmitted that cause infection and can lead to cervical cancer. HPV infection can cause cells to change to a precancerous state, sometimes eventually causing cervical intraepithelial neoplasia grade 3 (C1N3). After several years, HPV infection can progress to invasive cervical cancer. C1N3 is commonly the result of a specific human papillomavirus strain, known as HPV 16. Other cases of cervical cancer are associated with HPV 18. According to the National Cancer Institute, HPV 16 and HPV 18 account for 50 to 70 percent of cases of cervical cancer, respectively. There are, in all, 100 types of human papillomavirus.
Cell Changes That Lead to Cervical Cancer
Cancer is caused by abnormal cell growth, as is the case when cells in the cervix undergo abnormal growth from human papillomavirus. The first changes are referred to as dysplasia that is classified as mild, moderate or severe. Moderate and severe cervical dysplasias from HPV infection are most likely to lead to cervical cancer. There are other causes of cervical dysplasia other than human papillomavirus, a point worth noting, though HPV is the most common cause of dysplasia that leads to cervical cancer.
Risk Factors
Cervical cancer may or may not occur once a woman is infected with HPV. Risk factors for progression of HPV to cervical cancer include infection with the "high risk" HPV 16 or HPV 18. Compromised immunity, smoking, advanced age and HIV are also risk factors related to human papillomavirus and cervical cancer. High-risk human papillomavirus that persists is the most common cause of cervical cancer. HPV testing is important to detect changes in the cells of the cervix early, before cervical cancer develops. The HPV vaccine is an option for younger women, but should not replace regular examinations and screening for cervical cancer.
