This is a very common condition, and one of the most common problems that patients seek our help. A sebaceous cyst is a rounded swelling found underneath the skin over all hair bearing areas. It is especially common over the scalp and for men, the scrotum. It is not a tumour, though it may gradually increase in size. It is mostly painless unless it is infected.
It is also called an epidermal cyst, since it arises from the epidermis of the skin. Epidermis is the waterproof layer of our skin.
For most people, the cyst would not cause any symptoms. The person merely notices a painless lump underneath the skin. The lump may grow in size over time.
However when it is infected, it can be painful with redness and warmth of the overlying skin. Occasionally, a greyish-white cheese-like material may be seen discharging from the swelling. If the infection is serious, the entire lump may turn into an abscess, which can be extremely painful.
The doctor is usually able to clinch the diagnosis with just history taking and physical examination. Usually, no scans are needed. This is because a sebaceous cyst has some unique characteristics such as a bluish discolouration and the presence of a black pit in the centre. This pit is also called a punctum.
Soft and hard sebaceous cysts are benign and can be left alone. Sebaceous cyst does not become a cancer. Furthermore, most sebaceous cysts do not cause any symptoms. However, for the cysts that do cause problems or if the patient desires to treat it, sebaceous cyst removal through surgery is the definitive treatment. Surgery can be done as a simple day-surgery procedure under local anaesthesia.
When a swelling is acutely inflamed and infected, a course of antibiotics may be prescribed first to allow the inflammation to settle before surgery is performed. If the infection is very bad, the surgeon may do a simple procedure to allow the pus to be released first, and then follow-up with the definitive operation to remove the cyst when the infection has subsided. You should therefore see your doctor if your sebaceous cyst becomes acutely red, swollen and painful.
If you are not sure regarding the nature of a lump you noticed in your body, you should see a doctor to get an accurate diagnosis. This is especially important if the lump grows progressively bigger.
It is formed when the sebaceous gland that is found together with a hair follicle is blocked up by debris. The normal function of the sebaceous gland is to secrete sebum, which is an oily fluid so as to lubricate the skin and protect from dehydration.