Skin nonmelanocytic tumor
Cysts
Dermoid cyst
Authors: Ghassan A. Tranesh, M.D., Hong Qu, M.D.
Topic Completed: 1 January 2015
Minor changes: 12 July 2021
Copyright: 2002-2021, PathologyOutlines.com, Inc.
PubMed Search: Dermoid cyst [title] skin
Table of Contents
Definition / general | Sites | Pathophysiology | Clinical features | Radiology images | Case reports | Clinical images | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Differential diagnosisCite this page: Tranesh G. Dermoid cyst. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/skintumornonmelanocyticdermoidcyst.html. Accessed July 28th, 2021.
Definition / general
- Resembles keratinous cysts of epidermal type, but with hair adnexae
Sites
- Usually face of children along embryonic closure lines
- Also neck midline, nasal root, nose, forehead, mastoid area, anterior chest, scalp
Pathophysiology
- Dermoid cysts result from sequestration of cutaneous tissues along embryonal lines of closure
- Also encountered in deeper noncutaneous sites
- Some authors propose an embryological origin for these cysts, particularly in the nasal form
Clinical features
- Usually enlarges slowly, but sudden increase in size may occur, bringing the lesion to attention at a later age
- Treated with excision if clinically indicated
- Squamous cell carcinoma rarely develops in wall of cyst
- Infection of a cranial dermoid cyst may be complicated by central nervous system involvement
Radiology images
Images hosted on other servers:
CT without contrast shows
lateral dermoid cyst with
characteristic hyperdense cyst
wall and hypodense cyst cavity
Case reports
- 40 year old woman with dermoid cyst in eyelid (BMJ Case Rep 2013;2013;bcr2013200686)
- Midline cleft lip and nasal dermoids over five generations (Clin Dysmorphol 2006;15:155)
Clinical images
Images hosted on other servers:
Lower lid
Lateral eyebrow
Gross description
- Unilocular cysts are usually subcutaneous and filled with sebaceous material and hair
Microscopic (histologic) description
- Lined by stratified squamous epithelium with associated hair follicles and sebaceous glands
- Eccrine sweat glands present in 35%, apocrine glands in 15%
- Occasionally smooth muscle, but in contrast to benign cystic teratoma, cartilage and bone are not described
Microscopic (histologic) images
Images hosted on other servers:
Typical dermoid cyst
Keratin filled lumen
Kertinized stratified squamous lining
Positive stains
Differential diagnosis
- Congenital dermoid fistula
- Follicular cyst (infundibular type)
- Steatocystoma
- Vellus hair cyst
