Dermoid Cyst

Dermoid cysts are epithelial-lined cysts containing various appendageal structures resulting from retained epithelium along embryonic fusion planes. These cysts are either congenital or develop in childhood. The prevalence is equal in men and women.

CLINICAL FEATURES

Dermoid cysts are smooth, occur in the midline, and commonly possess a deep sinus tract that connects to the epidermis. They can measure between 1 cm and 4 cm, and are most commonly located on the forehead, lateral eye, or neck. A superficial dermoid cyst located on the dorsal nose is referred to as fistula of the dorsum of the nose and is characterized by a central tuft of hair or communication intracranially. Dermoid cysts can be located deep in the subcutaneous tissue, intracranially, or intraorbitally.

COMPLICATIONS

Infections, rupture, and abscess formation from the manipulation of these cysts are possible serious complications.

PATHOLOGY

Stratified squamous epithelium with a variety of adnexal structures may be present in the walls of dermoid cysts. Smooth muscle, pilosebaceous units, apocrine or eccrine glands, or goblet cells may also be present in the cyst walls. These cysts contain keratin and hairs.

DIFFERENTIAL DIAGNOSIS

The differential diagnosis of dermoid cysts includes gliomas, encephaloceles, hemangiomas, soft tissue sarcomas, and other epidermal cysts such as branchial cleft cysts and thyroglossal duct cysts.

TREATMENT

Imaging studies that help to characterize the extent of the tumor are necessary before excision is undertaken. Consultation with neurosurgery, otolaryngology, or plastic surgery may be indicated.