From the Guidelines
A sebaceous cyst, often referred to as an epidermoid cyst, consists of a wall made of epithelial tissue that encloses a collection of keratinous material, not sebum as commonly misconceived. According to the study published in Clinical Infectious Diseases 1, epidermoid cysts, which are frequently mislabeled as sebaceous cysts, contain skin flora in the cheesy keratinous material. This indicates that the primary composition of the cyst's contents is keratin, a protein found in skin cells, rather than sebum. The cyst wall, however, is indeed made of tissue, specifically epithelial cells.
The development of these cysts is related to the blockage or damage of skin structures, leading to the accumulation of keratinous material. While the term "sebaceous cyst" suggests involvement of sebaceous glands and sebum, the accurate description of these cysts highlights their composition and origin from epithelial cells and keratin accumulation.
Key characteristics and treatments of these cysts include:
- They are usually painless and harmless but may require medical attention if infected or cosmetically bothersome.
- Treatment often involves incision, evacuation of the contents, and sometimes probing the cavity to break up loculations, as outlined in the guidelines for managing skin and soft-tissue infections 1.
- The use of systemic antibiotics is rarely necessary unless there are signs of severe infection or compromised host defenses.
In clinical practice, understanding the true nature of these cysts as consisting of a tissue wall enclosing keratinous material is crucial for appropriate diagnosis and management, emphasizing the importance of evidence-based medicine in guiding treatment decisions.
From the Research
Composition of Sebaceous Cysts
- A sebaceous cyst is a type of cyst that consists of tissue, specifically a sac filled with a semi-solid substance called sebum 2.
- The cyst is usually filled with a thick, cheesy, white material that is made up of dead skin cells and oils from the skin 3.
- Sebaceous cysts are slow-growing, painless masses that can elevate the skin and often have a central punctum that represents the plugged orifice of the pilosebaceous follicle 4.
Histological Examination
- All cysts, including sebaceous cysts, should be examined histologically to determine their composition and to rule out any malignant changes 3.
- Histological examination can help to identify the type of cyst and to determine the best course of treatment 2.