An epidermoid cyst, sometimes known as a sebaceous cyst, is a firm, painless swelling under the skin that consists of a thin-walled sac full of yellow, cheesy material. As epidermoid cysts are not harmful and sometimes go away by themselves, most often no treatment is required. Occasionally, the cyst is troublesome because it catches on clothing, or it may become infected and sore, making cyst removal necessary. The procedure used to remove a cyst is known as epidermoid cyst excision, and it involves cutting out the cyst wall and its contents. Simply draining the cyst is not usually adequate, as this often leads to recurrence.
Surgery is the only option to remove an epidermoid cyst, as there are no effective medical procedures. Epidermoid cyst excision may be carried out using one of a number of different surgical procedures, but usually a local anesthetic is used, where the patient remains awake. The anesthetic is typically injected into the areas above, below and around the cyst. If a cyst has become infected, it is often treated with antibiotics and there is a delay to allow any inflammation to subside before excision is performed.
What is known as complete surgical excision involves extracting the cyst and its contents all at once. In what is called a minimal excision, the cyst contents are squeezed out before the wall is removed. Minimal epidermoid cyst excision is carried out through a small cut in the skin, but complete excision requires a larger incision which must be closed with stitches.
Following either of these operations, the walls of the cyst may be sent away for evaluation in a histology department, where the cells are examined microscopically. In extremely rare cases, a cyst may turn out to be cancerous. As epidermoid cysts are usually quite distinctive in their appearance, some doctors may not feel it is necessary to send an excised cyst for further study unless it appears suspicious.
After an epidermoid cyst excision, there is not usually any need for pain relieving medication and any bleeding that occurs can normally be dealt with by applying pressure to the wound for several minutes. The incision normally closes in around 48 hours, after which it is possible to uncover the wound and take baths or showers as usual. If stitches have been used, they are usually removed after a few days. It is important to be aware of any signs of infection, such as pain, redness or swelling, and any bleeding or discharge that is getting worse should be brought to the attention of a doctor.