Final answer:
A pilar cyst is a noncancerous, fluid-filled sac that commonly develops on the scalp and is form of a trichilemmal cyst. These cysts are filled with keratin and are typically slow-growing and painless, often requiring no treatment unless they cause discomfort or become inflamed.
Step-by-step explanation:
Description of a Pilar Cyst
A pilar cyst, also known as a trichilemmal cyst, is a benign, fluid-filled sac that develops under the skin, often on the scalp. These cysts originate from hair follicles, specifically from the outer hair root sheath. They are usually slow growing, painless, and can vary in size. Pilar cysts are typically filled with a thick, cheesy substance that is made up of keratin, the protein that makes up hair and nails. While they do not usually require treatment, they can be surgically removed if they become bothersome or inflamed.
Though not as familiar as ovarian cysts, that appear in organs like the ovaries as seen in conditions like polycystic ovary syndrome (PCOS), or as serious as cysts that can occur in the brain, like those seen with neurocysticercosis, pilar cysts are one of the common types of skin cysts. Unlike ovarian cysts which can have implications on fertility and overall health, or brain cysts which can lead to more severe symptoms, pilar cysts are generally considered a minor condition, unless complications arise.