Atlas of visual inspection of the cervix with acetic acid for screening, triage, and assessment for treatment

Whereas in CIN or AIS the disease is confined to the epithelium only, in invasive cervical cancers, the proliferating abnormal epithelial cells invade into the cervical stroma initially and may later spread to distant organs, a phenomenon known as metastasis. Most cervical cancers (80–90%) originate from the squamous cells and are known as squamous cell carcinomas. Adenocarcinomas arise from the columnar cells. Depending on the extent of the disease, cervical cancers are staged into stages I (the earliest stage, with disease confined to the cervix only) to IV (most advanced disease, with metastasis to other organs).

Treatment of invasive cancer depends on the stage of the disease. Whereas early-stage cancer is treated with surgery only, more advanced cancer requires treatment with a combination of chemotherapy and radiation therapy. Treatment with surgery is simpler than treatment with radiation and chemotherapy, and patients have fewer complications and a much better quality of life. Unfortunately, in most low- and middle-income countries more than 80% of patients are diagnosed at a stage when surgery is no longer feasible.