Cervical cancer is preceded by 10 to 15 years of precancerous lesions (dysplasia or CIN). These lesions are caused by a persistent virus called the Papilloma virus. Certain strains of this virus are potentially cancerous, or high cancer risk and are more dangerous vis a vis cancer than those we call low risk.
Cervical cancer detection is carried out either with an examination of precancerous lesions via a cytology smear (see the section smear test) or, more recently, with a high risk Papilloma virus detection test via a specific HPV test or a virological swab (see the section HPV).
In this situation, we are able to not just detect cancer but also prevent the development an invasive cervical cancer through diagnosis of the precursors of that cancer. Treatment allows for healing of any lesions without having to (or rarely) impact the uterus - a self-evident advantage in itself.
This detection method requires women to undergo regular smear tests between the ages of 25 and 65. It is recommended that women who have started having sex have a test every 3 years after their first two annual tests return normal results. In certain cases, where sexual activity starts very young the first smear test may be done at age 20.
Smear tests are not perfectly sensitive; sometimes abnormalities in the cervix are not detected (false negative results). This is another reason why it is important to keep having regular tests.
Today it is possible, when the smear is taken in a very fine layer (called a liquid medium), to check for abnormalities AND also test for the Papilloma virus. This way we can see if the person is carrying the high risk strain and we can adapt monitoring methods accordingly.