The two most common forms of benign skin cysts are epidermoid cysts and pilar cysts. These are often collectively referred to as "sebaceous cysts" as they look and feel similar and are treated in similar ways. However, they are very different from other forms of cysts, such as ganglion cysts, which are made up of joint fluid.
Epidermoid cysts are caused by some skin cells getting trapped under the skin. This can happen following a minor cut, from a blocked pore, or from body piercing.
Pilar cysts originate in the hair roots, and can happen spontaneously but are generally thought to be genetically inherited. Most pilar cysts occur on the scalp or other hair-bearing areas of the body.
Sebaceous cysts are benign and usually do not cause any discomfort or major functional limitation. They sometimes can drain spontaneously or become infected. If infected, often the cyst becomes suddenly more swollen, painful and red. The infection may be mild and resolve on its own or may be significant and require antibiotics +/- surgical drainage.
If a cyst has no history of significant infection, and is not causing any major functional problem, then removal is not covered by the Medical Services Plan of BC and patients have to pay privately if they wish to have it removed. Please see the following list of skin lesions and MSP coverage policy.
Surgery to remove a sebaceous cyst is done under local anesthetic in a minor surgery setting. Risks of the surgery can include bleeding, excessive scarring, recurrence (although rare), infection, anesthetic reaction, and wound healing complications.