A sebaceous cyst, also known as a skin cyst, is a growth beneath the skin that resembles a closed capsule. It is typically filled with liquid or semisolid substances, similar to a blister on the skin. These cysts can occur when oil glands or hair follicles in the skin become blocked or swollen, and there may also be a genetic component to their development. The main symptom of a skin cyst is a painless lump under the skin, which can become inflamed and tender.
Fortunately, sebaceous cysts are usually harmless and can be left untreated. However, if a small cyst becomes inflamed or a larger cyst causes discomfort, pain, or hair loss, it may be necessary to seek treatment to alleviate the symptoms.