Causes
We still don't fully understand what triggers cells to start dividing uncontrollably to form a tumor, but we have been able to observe certain patterns in people with cancer that tell us about risk factors.
Infection plays a major role in cervical cancer. The number one risk factor for cervical cancer is infection by the sexually transmitted human papillomavirus (HPV). Most cervical cancers are related to HPV - but not all HPV leads to cancer. In fact, infection with HPV rarely leads to cervical cancer; infection is a common occurrence and the virus usually goes away by itself. When cancer appears in the cervix, it's usually located at a site that's actively inflamed due to infection by this virus. Viruses insert their own DNA into human cells, altering their code. This may be what causes cells to multiply uncontrollably in cervical cancer.
It's been shown repeatedly that women who are young when they lose their virginity and women who have had many sexual partners are at higher risk of the disease.
People who smoke are at higher risk of this disease, as with most cancers. The risk also increases steadily with age. Women over age 65 are the most likely to develop cervical cancer.
There's limited evidence of elevated risk in certain families. It's likely that some cell types are more susceptible to HPV than others. Like many diseases, cervical cancer is probably caused by a combination of genetic and environmental factors.
Cervical dysplasia are new growths of abnormal tissue that often appear in the cervix and sometimes forewarn of cancer. Today, a classification system called the Bethesda system is used to describe abnormalities on the Pap test. Although it is much more complicated than the previous system, it is more specific and exact with its details. In the past, abnormalities were categorized as CIN (cervical intraepithelial neoplasm) grades I, II, and III, with grade III CINs the most likely to progress to cancer. Pap smears can detect CINs. Removing the CIN usually prevents cancer from developing at that site - and this was the biggest reason for the reduction in cervical cancer mortality in recent years.