Question: What is a Sebaceous Cyst?
Answer: A sebaceous cyst is a closed sac occurring just under the skin which contains a "pasty" or "cheesy" looking substance. A foul odor is also often present in the substance called keratin which fills sebaceous cysts. Keratin is a protein that creates the sac of cells called sebaceous cysts. The bumps or lumps you can feel under your skin are actually the sac of cells.
