Sebaceous Cysts

What are Sebaceous Cysts?

Sebaceous cysts swellings commonly occur on the skin can be simple sebaceous cysts. They vary in size, and are often small, like a grain of rice or sago. But they may grow and develop into large masses several centimetres in diameter. Generally the skin covering them is unaltered unless infection occurs. Then it may become inflamed, and the part tender. The scalp is a common site, and cysts frequently occur in groups. One or two or half a dozen or more may be scattered at irregular intervals over the scalp. The ear is another common site, especially just behind and just below the ear, or in the lobe.

They are also common on the back, and can silently grow to large proportions.

Sebaceous glands are normally located in the skin. They are tiny oil-producing factories, joined by a microscopic canal to the hair follicle below the skin surface. Oily material called sebum is produced in the gland. It tracks into the hair follicle, up the hair and on to the skin. Sebum gives hair its characteristic sheen. It also gives skin its oily texture, and keeps it moist. Without sebum the skin becomes hard and dry.

These glands are at maximum activity during the teen years. They play an active part in the cause of acne, and this can present a major problem to persons in this age group.

With increasing years they become inactive, and this accounts for the dry skin often complained of by older persons. The glands are in greatest concentration on the face, scalp and scrotum. They are present in lesser numbers on the upper part of the trunk. Excess production of sebum is called seborrhoea. This can produce a skin inflammation called “seborrhoeic dermatitis.” When the material dries out on the skin in excessive amounts it produces the characteristic flakes of dandruff.

Sometimes the duct becomes blocked. But sebum production continues. The gland swells as it becomes filled with the white fatty material.

Finally a cyst of increasing size is produced. As this continues it bulges upwards and outwards, and finally becomes apparent on the skin surface.

Sometimes infection gains entry to the cyst and an acute abscess forms.

Sebaceous Cysts Treatment

  • Simple squeezing. Although this is not recommended, most people will give the cyst a tentative squeeze. As this is done while bathing (when the skin is soft and warm), the contents often discharge. The sebum is usually foul-smelling, and comes away with a sudden popping sensation. However, unless the entire capsule is removed, it will promptly refill again.
  • Quite often medical assistance is sought. Either several squeezings have proved ineffectual over a period of months or years, or the cyst becomes infected, tender, red and painful. The doctor usually removes the cyst completely. This may be done under local anaesthetic in surgery. Large cysts or multiple ones are done in hospital, generally on an outpatient basis. General anaesthetic is seldom required. The entire cyst is removed, including the capsule. Often it is possible to remove this without breaking the cyst, but it frequently bursts partway through. A complete cure is usually affected with no recurrences in that particular area. If parts of the cyst remain, a recurrence is possible. Healing is generally rapid and complete. Antibiotics may be required if an infection is present.

Patients should be cautioned against: indiscreet interference with these cysts as infections may occur.