The cause of cervical cancer is oncogenic (cancer-causing) or high-risk types of HPV. An oncogenic HPV type is the cause, but it is not always capable of causing cancer on its own. The human body must allow it to do so.
How can HPV cause cancer?
High-risk types of HPV incorporate their DNA into the human cell DNA, causing mutations. It seems that this usually happens after a chronic or recurring infection of the epithelium.
You may have precancerous lesions for a long time and not be aware of it. They cause no symptoms! Precancerous lesions are treatable and you may prevent an invasive cancer by being careful. After treatment, however, there is a small chance of recurrence and you must continue to get check-ups.