What are epidermoid and pilar cysts?
A cyst is a sac that is filled with a fluid or semi-fluid material. Cysts develop in various places in the body and arise from different tissues in the body. Two of the most common types of cyst that occur under the skin surface are epidermoid and pilar cysts. These cysts used to be called sebaceous cysts but this term is no longer correct, as the origin of these cysts is not from the sebaceous glands in the skin (as was once thought). • An epidermoid cyst is a cyst where the cyst sac forms from cells that normally occur on the top layer of the skin (the epidermis). • A pilar cyst is a cyst where the cyst sac forms from cells similar to those that are in the bottom of hair follicles (where hairs grow from). In both cases the semi-fluid content of the cyst looks a bit like toothpaste. This substance is soggy keratin. Keratin is made by skin cells and is the substance that hairs are made from and the substance that covers the top layer of the skin.
