The Hair Loss Encyclopedia
non-cancerous, keratin-filled lumps typically found on the scalp
Trichilemmal cysts, also known as pilar cysts, are non-cancerous, fluid-filled lumps that typically develop on the scalp. They originate from the outer root sheath of hair follicles and are filled with keratin, a protein found in hair, skin, and nails. These cysts are usually firm, smooth, and can sometimes be hereditary.