Pilar Cyst

Pilar Cyst (Trichilemmal Cyst)

Overview

Pilar cysts (trichilemmal cysts) are common, benign, keratin-filled cysts that arise from the outer root sheath of hair follicles. They are the second most common type of skin cyst after epidermal inclusion cysts and occur predominantly on the scalp. They tend to run in families and may be multiple.

Key Symptoms

• Firm, smooth, round, mobile nodule under the skin
• Most commonly found on the scalp
• Skin-colored, typically without a central punctum
• Usually 1-4 cm in diameter
• Painless unless inflamed or traumatized
• Often multiple, and may run in families

Affected Areas

Scalp (90% of cases), Neck, Face, Trunk

Care Instructions

1. No treatment is required for asymptomatic pilar cysts.
2. Avoid picking, squeezing, or traumatizing the cyst.
3. See a dermatologist if the cyst becomes painful, inflamed, or is cosmetically bothersome.
4. Surgical excision is the standard treatment and is often straightforward on the scalp.
5. The cyst wall must be completely removed to prevent recurrence.
6. Inform your dermatologist if you have a family history of pilar cysts.

Medical Disclaimer: This information is for educational purposes only and does not replace professional medical advice. Always consult a qualified dermatologist for diagnosis and treatment.

Prevalence: Common; occurs in 5–10% of the population, more often in women