Cyst

A cyst is a closed sac, having a distinct membrane and division compared with the nearby tissue.

It is a cluster of cells that has grouped together to form a sac however an aspect of a cyst is that the cells forming the "shell" of such a sac are distinctly abnormal when compared with all surrounding cells for that given location.

It may contain air, fluids, or semi-solid material. A collection of pus is called an abscess, not a cyst. Once formed, sometimes a cyst may resolve on its own. When a cyst fails to resolve, it may need to be removed surgically, but that would depend upon its type and location.

Cyst Media

Relative incidences of different types of ovarian cysts
Relative incidence of odontogenic cysts

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