What is the Difference Between Dermoid and Epidermoid Cyst

The key difference between dermoid and epidermoid cyst is that a dermoid cyst is a noncancerous lump that commonly forms on the head, neck, ovaries, or spine, while an epidermoid cyst is a noncancerous lump that commonly forms on the face, neck, chest, upper back, scrotum, and genitals.

Dermoid and epidermoid cysts are slow-growing benign cysts. They typically occur in the scalp and the skull of infants and young children. An epidermoid cyst is lined with stratified squamous epithelium as a dermoid cyst. However, epidermoid cyst does not contain additional skin appendages that are less likely to rupture.

CONTENTS

1. Overview and Key Difference
2. What is a Dermoid Cyst
3. What is an Epidermoid Cyst (Sebaceous Cyst)
4. Similarities – Dermoid and Epidermoid Cyst
5. Dermoid vs. Epidermoid Cyst in Tabular Form
6. Summary – Dermoid vs. Epidermoid Cyst

What is a Dermoid Cyst?

A dermoid cyst is a lump or bump that contains a greasy yellow material, bone, fluid, hair, nerves, and skin. This condition is frequently identified in children under the age of 5 and is also found in around 4 out of 10 dermoid cysts present at birth. Dermoid cyst occurs when skin and skin structures become trapped during the fetal development phase. Moreover, the signs and symptoms of a dermoid cyst may include a lump near the edge of the eyebrow that is swollen and has a yellow tint, pain in the pelvic area, especially around the time of menstruation, trouble walking, urinary incontinence, and weakness in legs and arms.

Dermoid cysts can be diagnosed through physical examination,  CT (computed tomography) scan or magnetic resonance imaging (MRI), and pelvic ultrasound or transvaginal ultrasound. Furthermore, treatment options for dermoid cysts may include pain medications, removing a cyst through a small incision, minimally invasive surgery (ovarian cystectomy), and microsurgery to remove a cyst in the spine.

What is an Epidermoid Cyst?

An epidermoid cyst is a small bump beneath the skin that commonly appears on the face, neck, and trunk. It is also known as a sebaceous cyst. It is made up of encapsulated subepidermal nodules filled with keratin. Therefore, the build-up of trapped keratin usually causes the epidermoid cyst. Sometimes, these cysts are formed due to irritation or injury of the skin or the most superficial portion of a hair follicle. Moreover, the signs and symptoms of this condition may include a small, round lump or bump under the skin, a tiny blackhead plugging the central opening of the epidermoid cyst, a thick, yellow, smelly material draining from the cyst, redness, swelling, and tenderness in the area of the cyst.

Epidermoid cysts can be diagnosed through physical examination and skin biopsy. Furthermore, treatment options for epidermoid cysts may include steroid injections to reduce swelling and inflammation, incision, drainage, and minor surgery.

What are the Similarities Between Dermoid and Epidermoid Cyst?

• Dermoid and epidermoid cysts are slow-growing benign cysts.
• Both occur in the scalp and the skull of infants and young children.
• They are lined with stratified squamous epithelium.
• Both can be diagnosed through physical examination.
• They can be treated through surgical procedures.

What is the Difference Between Dermoid and Epidermoid Cyst?

A dermoid cyst is a noncancerous lump that commonly forms on the head, neck in ovaries, or on the spine, while an epidermoid cyst is a noncancerous lump that commonly forms on the face, neck, chest, upper back, scrotum, and genitals. Thus, this is the key difference between dermoid and epidermoid cyst. Furthermore, a dermoid cyst occurs when the skin and skin structures become trapped during the fetal development phase. On the other hand, an epidermoid cyst occurs when trapped keratin is built up due to irritation or injury of the skin or the most superficial portion of a hair follicle.

The infographic below presents the differences between dermoid and epidermoid cyst in tabular form for side-by-side comparison.

Summary – Dermoid vs. Epidermoid Cyst

A cyst is a lump or bump that may contain fluid or other material. Dermoid and epidermoid cysts are slow-growing noncancerous cysts usually seen in children. Both are lined with stratified squamous epithelium. However, dermoid cyst contains a greasy yellow material, bone, fluid, hair, nerves, and skin, while epidermoid cyst contains encapsulated subepidermal nodules filled with keratin. Moreover, dermoid cyst commonly develops on the head, neck, ovaries, or spine, while epidermoid cyst commonly develops on the face, neck, chest, upper back, scrotum, and genitals. So, this summarizes the difference between dermoid and epidermoid cyst.

Reference:

1. “Dermoid Cyst: Causes, Symptoms and Treatment.” Cleveland Clinic.
2. “Epidermoid Cyst.” Statpearls – NCBI Bookshelf.

Image Courtesy:

1. “Limbal dermoid cyst in child” By Community Eye Health (CC BY-NC 2.0) via Flickr
2. “Inflamed epidermal inclusion cyst” By Steven Fruitsmaak – Own work (CC BY-SA 3.0) via Commons Wikimedia