Sebaceous Cysts

A sebaceous cyst, also known as an epidermoid cyst or cutaneous cyst, is a benign, closed sac that forms beneath the skin. It is typically filled with a thick, oily substance called sebum, which is produced by sebaceous glands that help lubricate the skin. These cysts are common and usually develop on the face, neck, or torso, though they can appear anywhere on the body. While generally harmless, they can become infected, inflamed, or painful if left untreated.

Visible lump: The most common symptom is a small, round bump beneath the skin, often the size of a pea or larger.
Soft, movable: Sebaceous cysts are typically soft and can be moved slightly under the skin.
Painless or mild discomfort: Most sebaceous cysts are painless, but they can become tender or painful if they become infected or inflamed.
Pus or foul-smelling discharge: If the cyst ruptures or becomes infected, it may discharge pus or a thick, yellowish substance that may have a foul odor.

Blocked sebaceous glands: The most common cause of a sebaceous cyst is the blockage of a sebaceous gland or hair follicle. When the gland becomes obstructed, sebum cannot escape and accumulates, forming a cyst.
Acne: People with acne or oily skin may be at higher risk for developing sebaceous cysts, as clogged pores are common.
Infections: Bacterial infections can cause the sebaceous gland to become inflamed, leading to cyst formation.

Observation: In many cases, if the cyst is small, painless, and not causing any problems, no treatment may be necessary. The cyst can simply be monitored for changes.
Incision and drainage: If the cyst becomes painful or infected, a doctor may drain the contents of the cyst by making a small incision in the skin. However, this procedure often does not remove the entire cyst, and the cyst may recur.
Surgical removal: The most effective treatment for a sebaceous cyst is complete surgical removal. This involves removing both the cyst and its wall to prevent it from returning. This is typically done in an outpatient setting under local anesthesia.