What is a trichilemmal cyst and where does it form?
A trichilemmal cyst is a common cyst that forms from the outer root sheath of a hair follicle. It appears as a silent, smooth, and mobile lump on the scalp in 90% of cases.
Common questions about Trichilemmal cyst
Short answers, pulled from the story.
How does a trichilemmal cyst differ from an epidermoid cyst?
A trichilemmal cyst lacks a granular cell layer, which distinguishes it from an epidermoid cyst. This microscopic detail confirms its unique origin from the outer root sheath of the hair follicle.
Why are trichilemmal cysts often mistaken for sebaceous cysts?
Medical professionals have used the term sebaceous cyst to describe trichilemmal cysts for decades despite the fact that they are not true sebaceous cysts. True sebaceous cysts originate from sebaceous glands and contain sebum, while trichilemmal cysts contain keratin.
Can a trichilemmal cyst turn into a tumor?
In rare cases, a trichilemmal cyst can undergo a transformation into a proliferating trichilemmal tumor. This benign but potentially aggressive growth mimics the behavior of cancer and may require extensive treatment.
How is a trichilemmal cyst treated by physicians?
Most physicians perform the procedure under local anesthetic to remove the cyst. Treatment options range from minimal excision to formal surgical excision depending on the cyst's size and wall thickness.
What causes trichilemmal cysts to appear on the scalp?
Evidence suggests that trichilemmal cysts are produced by budding from the external root sheath as a genetically determined structural aberration. This genetic predisposition explains why 90% of cases occur on the scalp where hair follicles are most concentrated.