Also called epidermal cyst or keratin cyst, a sebaceous cyst is a sac-like swelling arising from a hair follicle. A skin trauma can also induce a cyst to form. It normally contains a cheese like substance of keratin (a protein) inside. The sebaceous cysts usually occur on the back, the scalp of head, neck, face and genital area. They are of different sizes.
- Damage to the hair follicles- Each hair grows from a follicle which can be damaged from the injuries, like abrasions, or surgical wounds. It can also become blocked by surface cells.
- Ruptured sebaceous gland- Sebaceous glands produce sebum, oil, which lubricates the skin and coats the hair shaft. These glands can be easily ruptured by inflammatory skin conditions, changing them into sebaceous glands.
- Heredity- Sebaceous cysts can be inherited associated with some hereditary syndromes.
- Developmental defects- They can begin in a developing fetus when stem cells intended to form skin, hair or nails become trapped in cells that form other tissues.
- High levels of testosterone- It may also be responsible for sebaceous cysts.
Symptoms and signs-
Normally, they are painless and slow-growing. The skin over them can be moved. Sometimes they get infected and due to infection, they become tender and painful. When inflamed, the skin over them will become red.
They may rupture causing erythema, swelling, and pain. Complications can also take place after surgical removal, which include bleeding, infection, and scaring. Erythema and pain can be managed with intralesional triamcinolone. Infection following surgery can be prevented by using proper aseptic techniques.
Though recognized as a benign cyst, rarely malignancy may occur. Squamous cell carcinoma (SCC) is the most common malignancy followed by basal cell carcinoma (BCC). In developing malignancy, squamous cell carcinoma occurs approximately 70% of the time.
A doctor can diagnose after examining it. No special tests are required for its diagnosis.
Sebaceous cysts are harmless but merely a cosmetic annoyance. That is why their treatment is often ignored for a long time by the patients. The patient usually seeks treatment for cosmetic reasons or when it becomes troublesome due to repeated infections.
If the cyst becomes infected, it will have to be treated with a course of suitable antibiotics.
The only suitable treatment of the sebaceous cyst is surgical excision, in which it is excised along with the removal of the sac. If the sac is not removed properly, there are chances of its recurrence.
Sebaceous cysts are not so commonly prevalent. They are filled with a cheese-like substance of keratin. They usually occur on the back, neck, scalp, face and genital area. They are of different sizes.
Sebaceous cysts are acquired but they may be associated with some hereditary syndromes.
They are slow to grow and are likely to become infected. When infected, they are tender and painful.
The treatment includes administration of suitable antibiotics when the sebaceous cyst is infected. Its only suitable treatment is surgical excision along with the removal of the sac.