Something else? Ask Aunt Vadge – bottom left of your screen!
An epidermoid cyst is a small, keratin-filled sac lined by skin (epidermis). It forms when a hair-follicle opening becomes blocked, or when a fragment of skin gets trapped under the surface after an injury.
Vulvar epidermoid cysts may also be called epidermal inclusion cysts or, misleadingly, sebaceous cysts – though they are not actually from the sebaceous (oil) gland.
Epidermal, epidermoid and inclusion cyst are all names for the same thing – a keratin-filled sac lined by skin, not a sebaceous gland. These cysts can also develop inside the vagina.
Epidermoid cysts are the most common type of vulvar cyst. They are benign, and usually filled with soft, cheesy keratin rather than fluid. They are most often found around the vulva, near the vaginal entrance, most often in adults, but sometimes in children.1,2
Most sebaceous cysts are small and asymptomatic; however, these types of cysts can grow large and cause pain. Vulvar sebaceous cysts can occur in any person, without seeming preference for ethnic background, age, or location.
Symptoms of a vulvar sebaceous cyst
- A small bump, sometimes more than one, filled with soft keratin
- Various sizes from a few millimetres
- May be red and tender
- Large cysts may cause discomfort and pain
- Thick, cheesy material may drain, and it can smell bad
- Tampons and sex may cause pain
- Walking or sitting may be uncomfortable
- Cysts may cause itching and pain when urinating
What causes sebaceous cysts of the vulva?
Vulvar epidermoid cysts form when a hair-follicle opening becomes blocked, or when skin cells get trapped under the surface, and keratin gradually builds up inside the sac. These cysts may appear by themselves or in clusters. They are not sexually transmitted or caught from another person via towels, sheets, or clothes.
Irritants such as creams, douches, soaps, and scented or printed toilet paper can inflame the vulva (contact dermatitis), so they are worth avoiding – though they are not what causes the cyst itself.3,4,5,6
Treatment of vulvar sebaceous cysts
The most common course of action is to take no action, unless the cyst is causing pain and discomfort. Keeping the area clean with warm water and a soft cloth is gentle and sensible, though a true cyst won’t simply wash away.
These cysts are not dangerous and do not tend to be infected. If a cyst is bothersome, a clinician may drain or remove it.
Warm sitz baths can soothe the area, but don’t try to squeeze or burst the cyst yourself – that risks infection, and it tends to come back if the sac is left behind. Topical creams or gels may also be prescribed.
Diagnosis of a vulvar sebaceous cyst
A physician will do a pelvic examination and take a medical history. Typically, an examination is sufficient to diagnose a sebaceous cyst; however, further testing may be necessary to rule out any potential infections.
A biopsy may be taken to rule out any underlying issues. A sample of fluid from the cyst may be taken for examination.
Frequently asked questions
What is a vulvar epidermoid cyst?
It is a small, benign lump under the vulval skin – a sac lined by skin and filled with soft keratin. It forms when a hair-follicle opening gets blocked or a fragment of skin is trapped after injury, and it is the most common type of vulvar cyst. (‘Sebaceous cyst’ is a common but inaccurate name for it.)
Are vulvar cysts dangerous?
Usually not. Most are small, painless and harmless, and often need no treatment. See a clinician if a lump grows, becomes painful or red, or starts draining, so it can be checked and, if needed, drained or removed.
How do you get rid of a vulvar cyst?
Small, painless cysts are usually left alone. Warm sitz baths can soothe discomfort, but don’t squeeze or burst a cyst yourself. A persistent or infected one is best drained or fully removed by a clinician.
This article is general information and not a substitute for personalised medical advice. If you have a vulval lump that is painful, growing or draining, please see an experienced practitioner.
- Sand FL, Thomsen SF. Clinician’s Update on the Benign, Premalignant, and Malignant Skin Tumours of the Vulva: The Dermatologist’s View. International Scholarly Research Notices. 2017;2017:1–10.
- McNeeley SG. Vulvar inclusion and epidermal cysts. MSD Manual (Consumer Version).
- Gokdemir G, Baksu B, Baksu A, Davas I, Koslu A. Features of patients with vulvar dermatoses in dermatologic and gynecologic practice in Turkey: is there a need for an interdisciplinary approach?. J Obstet Gynaecol Res. 2005 Oct. 31(5):427-31.
- Margesson LJ. Contact dermatitis of the vulva. Dermatol Ther. 2004. 17(1):20-7.
- Marren P, Wojnarowska F, Powell S. Allergic contact dermatitis and vulvar dermatoses. British Journal of Dermatology. 1992;126(1):52–56.
- Nardelli A, Degreef H, Goossens A. Contact allergic reactions of the vulva: a 14-year review. Dermatitis. 2004 Sep. 15(3):131-6.
