A sebaceous cyst is basically a sac that is lined by cells that secrete keratin, or in simple terms - its a keratin cyst. It does not secrete sebum or oil as the name suggests.
Although a sebaceous cyst can happen anywhere on the body, the common areas are back, face, chest etc. Its generally better felt than seen. It is seen as a tiny bump with a black colored opening. Some people can also appreciate that on pressing, a toothpaste colored substance oozes out.
Generally, sebaceous cysts are left alone, unless they get repeatedly infected.
Sebaceous cyst excision is a simple surgery to remove the entire sac and its contents. The area to be treated is numbed with a local anesthetic, the skin is opened, the cyst dissected and isolated completely, its stalk crushed and the cyst removed. A stitch or two may be required depending on the size of they cyst.
The client is sent back home with a list of post procedure instructions.