Pilar cyst

A pilar cyst, also known as a trichilemmal cyst, is:

  • A benign, non-cancerous growth

  • Derived from hair follicles

  • Typically occurs on the scalp

  • Filled with a thick, yellowish material (keratin)

Characteristics

  • Firm, round, or oval bump

  • Usually 1-5 cm in size

  • May become inflamed or infected

Treatment

  • Surgical removal (excision)

  • Recurrence is common if not completely removed

Pilar cysts are usually harmless but can cause discomfort or become unsightly.