Diagnosis and treatment of benign fluid- or keratin-filled skin cysts.
Benign Growth
A skin cyst is a closed, sac-like pocket under the skin filled with fluid, air, or semi-solid material, most often keratin. The most common type dermatologists see is the epidermoid cyst (sometimes called a sebaceous cyst), which forms a smooth, movable lump that can slowly grow over months or years.
A blocked hair follicle or oil gland traps skin cells and debris beneath the surface, which then continue to accumulate inside a sac.
Most cysts cannot be reliably prevented, though keeping skin clean and avoiding repeated trauma to the same area can lower the risk for some types.
Small, asymptomatic cysts can often be left alone. Larger or bothersome cysts are typically treated with in-office drainage or surgical excision, which removes the entire sac to prevent recurrence.
Myth: Squeezing a cyst at home will get rid of it. Fact: Squeezing usually leaves the sac wall behind, so the cyst almost always returns, often alongside a painful infection.
If a cyst becomes red, painful, or rapidly enlarges (a possible sign of infection), or if you want it removed.