Cancer is actually a group of many related diseases that all have to
do with cells. Cells are the very small units that make up all living
things, including the human body. There are billions of cells in each
person's body.
Cancer happens when cells that are not normal grow and spread very
fast. Normal body cells grow and divide and know to stop growing. Over
time, they also die. Unlike these normal cells, cancer cells just
continue to grow and divide out of control and don't die.

Cancers are characterized by the cells that they originally form from.
The most common type of cervical cancer is called squamous cell
carcinoma; it comes from cells that lie on the surface of the cervix
known as squamous cells. Squamous cell cervical cancer compromises
about 80% of all cervical cancers. The second most common form is
adenocarcinoma; it comes from cells that make up glands in the cervix.

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