Pilar cyst is also known as what?

• A. Lipoma
• B. Epidermoid cyst
• C. Wen
• D. Ganglion

Answer: (C)

Pilar cyst is a trichilemmal cyst arising from the hair follicle outer root sheath, most often on the scalp. In classic clinical terminology, this lesion is called a wen. The name reflects the historic, more layperson-friendly terms used for such scalp cysts. This cyst is lined by squamous epithelium showing trichilemmal keratinization (no granular layer) and filled with compact keratin, distinguishing it from epidermoid cysts, which have a granular layer in the lining and different content. Lipomas are fatty tumors, and ganglions are joint-related cysts, neither of which describe pilar cysts. So wen is the best label for a pilar cyst.