According to the National Cancer Institute, 11,000 women are diagnosed with cancer of the cervix every year and most commonly occurs in women younger than 55 years of age. Cervical cancer involves the transformation of the cells of the cervix, which is the bottom portion of a woman's uterus that opens to the vagina. The American Cancer Society reports that there are two main types of cervical cells: squamous cells and glandular cells. When either or both of these cells transform into cells that grow uncontrollably, the result is cervical cancer.
Squamous Cell Carcinoma
The American Cancer Society notes that squamous cells are a type of thin flat cell that cover the ectocervix, the portion of the cervix that is nearest the vagina. They also report that 80 to 90 percent of cervical cancers are squamous cell carcinoma. This type of cancer generally begins where the ectocervix meets the endocervix, the portion of the cervix closer to the uterus. This area where the two regions meet is called the transformation zone. The squamous cells in the transformation zone are most likely to turn into squamous cell carcinoma of the cervix.
Adenocarcinoma
Adenocarcinoma accounts for about 10 to 20 percent of all cases of cancer of the cervix. Adenocarcioma stems from the glandular cells of the endocervix. Glandular cells in the cervix secrete mucus, which lubricates the vagina. While squamous cell carcinoma of the cervix is currently much more common, adenocarcinoma cases are becoming more and more common, especially in women 20 to 30 years old, according to the American Cancer Society.
Adenosquamous Carcinomas
Though adenocarcinomas and squamous cell carcinomas individually account for most of the cases of cervical cancers, some women have a type of cervical cancer with features of both of these cells. The Abramson Cancer Center of the University of Pennsylvania reports that 3 to 5 percent of cervical cancer cases have cancer with characteristics of both adenocarcinoma and squamous cell carcinoma. This type of cervical cancer is called adenosquamous carcinomas. The American Cancer Society adds that this type of cancer is also sometimes called "mixed carcinoma."
