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The two main types of cervical cancer are classified by the cells’ appearance under a microscope. They include:

• Squamous cell carcinoma. According to the American Cancer Society (ACS), approximately 80 to 90 percent of cervical cancers are squamous cell carcinomas. The cells that compose these cancers resemble the thin, flat squamous cells that line the surface of the endocervix (the part of the cervix that is closest to the uterine body). Squamous cell carcinomas typically begin where the endocervix and ectocervix (the part of the cervix that is next to the vagina) converge.
  
  
• Adenocarcinoma. These cancers account for the remaining 10 to 20 percent of cervical cancers, according to the ACS. Adenocarcinomas, which develop from the gland cells that produce mucous in the endocervix, are becoming more common in patients born in the last 20 to 30 years.

On occasion, cervical cancers possess features of both adenocarcinomas and squamous cell carcinomas. These rare cancers are called adenosquamous or mixed carcinomas.