epidermoids

Epidermoids are a type of benign skin cyst. They arise from the epidermis, the outermost layer of the skin, and contain keratin, a protein found in skin, hair, and nails. Epidermoid cysts are typically slow-growing and can appear anywhere on the body, though they are most common on the face, neck, and trunk. They often present as a firm, dome-shaped lump under the skin, which may or may not have a small dark pore in the center. The cyst wall is made of epidermal cells, and the contents are a cheesy or pasty material composed of keratin and skin debris.

These cysts are formed when epidermal cells are somehow trapped beneath the skin's surface. This can happen due to a variety of reasons, including trauma to the skin, blockages of hair follicles, or developmental anomalies. While generally harmless, epidermoid cysts can sometimes become inflamed or infected, leading to pain, redness, and swelling. If a cyst becomes infected, it may rupture, releasing its contents and potentially causing further inflammation.

Diagnosis is usually made through a physical examination. In some cases, a biopsy may be performed to confirm the diagnosis and rule out other skin conditions. Treatment is typically not necessary unless the cyst is causing discomfort, is a cosmetic concern, or becomes infected. The most common treatment involves surgical excision, where the entire cyst, including its wall, is removed to prevent recurrence. Draining the cyst is usually not recommended as it often leads to re-formation.