A sebaceous cyst (also called Epidermal cyst; Keratin cyst or Epidermoid cyst) is generally a nontender, small lump beneath the skin.
Redness, tenderness, or increased temperature of the skin over the area may occur if infection is present. If the skin/cyst is in any way punctured a grayish-white, cheesy, foul-smelling material may drain from the cyst.
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