The actual site of cervical cancer is mostly at the junction of the vaginal part of the cervix, the squamous epithelium and the tubular cortex of the cervix. Under the stimulation of carcinogenic factors, cervical squamous epithelial basal cells are actively proliferating and poorly differentiated, gradually forming cervical epithelial atypical hyperplasia, which can gradually develop into carcinoma in situ. Early infiltrative carcinoma and atypical hyperplasia are pre-cancerous lesions, which can exist for a long time, averaging about 4 years to return to normal, and can also develop into carcinoma in situ. Both atypical hyperplasia and carcinoma in situ are confined within the cervical epithelium and are often referred to as squamous intraepithelial lesions of the cervix to distinguish them from invasive carcinoma. The progression from atypical hyperplasia to invasive carcinoma is slow and progressive, usually taking 8-10 years. Once infiltrating carcinoma forms, it grows particularly rapidly, and if not treated promptly, patients can die within 2-5 years.