Dermoid Cyst: Types, Presentation and Treatment

Last Updated on April 25, 2025

A dermoid cyst of skin is a slow-growing cystic mass that is lined by epithelium (skin] and is filled with old skin cells that are grossly seen as pultaceous or toothpaste-like material.

All these lesions have a similar histology of a lining of the dermis that contains stratified squamous epithelium with hair follicles and sebaceous glands, and a cavity that contains keratin, a type of protein. It arises due to the entrapment of ectodermal elements. Inside, it may have hair, fat, bone fragments, or even sweat glands [1]. The ectoderm is the outermost of the three primary germ layers of an embryo. It gives rise to structures such as the epidermis, the nervous system, the brain, parts of the eyes, and ears.]

The term dermoid cyst may represent a lesion across various systems of the body.  It may refer to a cystic lesion of the skin,  spine or skull or ovary.

Dermoid cysts develop during fetal life when skin layers fail to fold properly, trapping tissues in abnormal locations. Dermoid cysts are considered to represent up to about 60 percent of scalp and skull masses in children. Most of these lesions are congenital but are often not diagnosed at birth as they may appear late. The lateral aspect of the upper eyelid is the most common region of occurrence. These occur less commonly in the

Common Sites Where Dermoid Cysts Occur

• Face and Neck: Near the eyes, nose, or neck area(cutaneous). Can also occur in mid-chest region, sacrum, and perineal area.[1].
• Ovaries: Known as ovarian dermoid cysts or mature cystic teratomas [2].
• Spinal Cord
• Scalp or Chest
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Clinical Presentation

The cutaneous dermoid cyst is usually a flesh-colored, noncompressible subcutaneous nodule. It is usually not tender to touch.

Most dermoid cysts are painless and grow slowly. Many are only noticed when they start to cause visible swelling or cosmetic concerns [1].

Common symptoms include:

• A firm, round lump under the skin
• Movable under gentle pressure
• Usually painless unless infected
• May cause pressure effects depending on location (for example, visual disturbances if near the eye)
• In the case of ovarian dermoid cysts, symptoms like pelvic pain, bloating, or irregular periods may occur [2].

The protrusion of hair is pathognomonic. The cysts may lie dormant for a long period and then enlarge, resulting in clinical manifestations. Midline cysts have the highest association with cranial or spinal dysraphism. These are also more likely to have intracranial extension. Multiple cysts have also been reported.

Diagnosis

The diagnosis is done by

• Physical examination (esp. for surface lumps)
• Ultrasound imaging to evaluate soft tissue characteristics [3]
• CT scan or MRI for deep, large, or sensitive locations like the brain or spinal cord [1]

Biopsy is rarely needed unless there are unusual features suggesting other conditions.

Treatment

Treatment depends on the cyst’s size, location, and symptoms.

• Observation: Small, harmless cysts without symptoms may just be monitored [1].
• Surgical Removal: If the cyst grows, becomes infected, causes cosmetic concerns, or presses on nearby structures, surgical excision is the treatment of choice. Superficial cysts require simple  excision  [4], whereas specialized surgery is required for deep cysts (e.g., spinal or ovarian) [2]
• Laparoscopic Surgery: A minimally invasive technique often used for ovarian dermoid cysts [2].

Complete removal is important to prevent recurrence.

Complications

Although dermoid cysts are benign, they can cause issues like

• Rupture: They rupture internally (especially ovarian cysts), causing severe pain [2]
• Infection: They get infected, leading to redness, swelling, and tenderness [4]
• Mass effect: Rarely, they cause pressure effects on nearby structures, especially in the head and spine [1]
• Malignant Change: Exceedingly rare but has been documented in some ovarian dermoid cysts [2].

Other Similar Cutaneous Cysts

Some other cysts may seem like dermoid cysts, and there is often confusing literature available using interchanging names and nomenclature.  For example, some articles consider epidermal inclusion cysts or sebaceous cysts the same as dermoids, but there is a difference at the histological level, and we will discuss that now.

Epidermal Inclusion Cyst

Epidermal inclusion cyst is also widely known as a sebaceous cyst or epidermoid cyst. Because of the similarities of the names, dermoid and epidermoid cysts may be thought to represent one entity.
The cyst appears similar clinically, and this further complicates the matter.

Epidermal inclusion cyst is different from dermoid cyst, and the difference is based on histological features.

Trichilemmal Cyst

It is also known as a pilar cyst. Trichilemmal cyst is a keratin-filled cyst that originates from the hair root sheath. It is commonly seen in the scalp.

It has stratified squamous epithelium lining and contains keratin. The treatment is excision.

References

1. Kumar V, Abbas AK, Aster JC. Robbins Basic Pathology. 10th ed. Elsevier; 2017.
2. Menke J, Schwarz A. Ovarian dermoid cyst with teeth. BMJ Case Rep. 2013 Aug 7;2013:bcr2013010271. [Link]
3. MedlinePlus. Dermoid Cysts. U.S. National Library of Medicine. [Link]
4. Prior A, Anania P, Pacetti M, Secci F, Ravegnani M, Pavanello M, Piatelli G, Cama A, Consales A. Dermoid and Epidermoid Cysts of Scalp: Case Series of 234 Consecutive Patients. World Neurosurg. 2018 Dec;120:119-124. [Link]