Trichilemmal Cyst
A benign hair follicle-derived cyst most commonly occurring on the scalp, requiring complete wall excision to prevent recurrence.
Full Definition
Trichilemmal cyst is a common benign cystic lesion derived from the outer root sheath of hair follicles, most frequently presenting as a solitary, mobile, subcutaneous nodule on the scalp. These cysts are often familial and may be multiple, containing keratin debris without the granular layer seen in epidermoid cysts. Complete surgical excision including the entire cyst wall is essential to prevent recurrence. The cysts may rupture spontaneously, leading to inflammation and making subsequent surgical removal more challenging.
Usage
Usage note: Pilar cyst is an acceptable alternative term, though trichilemmal is more precise.
In Context
- "Complete excision of the trichilemmal cyst was performed with intact cyst wall removal." — Operative note
- "Multiple trichilemmal cysts were noted consistent with familial pilar cyst syndrome." — Clinical examination