Table of Contents
Definition / general | Terminology | Epidemiology | Sites | Pathophysiology | Clinical features | Diagnosis | Radiology description | Radiology images | Case reports | Treatment | Clinical images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Differential diagnosis | Additional referencesCite this page: Morrison A. Dermoid cyst. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxilladermoid.html. Accessed March 27th, 2023.
Definition / general
- Cystic structure lined by stratified squamous epithelium
- Cyst lining contains sebaceous glands, hair follicles / shafts, eccrine sweat glands / coils
- Cyst contain keratinaceous, caseous, sebaceous or purulent debris with hair, nails, fat or cholesterol clefts
Terminology
- Dermoid cyst: lined by stratified squamous epithelium with adnexae (hair follicules, sweat glands, sebaceous glands)
- Epidermoid cyst: stratified squamous epithelial lining without adenexae
- Teratoma: can be cystic but must have all three germinal layer represented within cyst wall, namely ectoderm (skin, hair, teeth), mesoderm (skeletal muscle, vasculature, CNS, peripheral nerves), endoderm (thyroid, GI tract components, lung, liver)
Epidemiology
- Dermoid cysts: typically are present from birth
Sites
- In head and neck lesions, traditional dermoids are deeply situated adherent to periosteum; most common site is soft tissue of floor of mouth
- Intraosseous lesions are extremely rare; more common in maxilla than mandible
Pathophysiology
- Traditional dermoid cyst: arises from sequestered ectoderm along fusion lines of embryonic processes
- Intraosseous dermoid cysts of jaw bones have debatable pathophysiology:
- Leading theory is a sequestration of Wikipedia: Stomodeum [Accessed 11 June 2018] ectoderm trapped in deep tissues along fusion lines of embryonic processes and embedded into developing bone during embryogenesis
- Could be dermal metaplasia of an odontogenic cyst (especially when found in association with a tooth) or epithelial remnant; however the squamous epithelium and adnexal structures are typically more organized and well formed than would be expected of metaplastic tissue
- Dermoid cysts with only sebaceous glands: argued to be orthokeratotic variant of keratocytic odontogenic tumor (formerly odontogenic keratocyst) with sebaceous differentiation and not a true dermoid cyst
Clinical features
- Often asymptomatic swelling but may have pain related to swelling
- Deformity due to mass effect can occur with larger lesions
Diagnosis
- Often not correctly diagnosed until histopathological examination is complete
Radiology description
- Radiolucent unilocular lesion
Radiology images
Case reports
- 20 year old man with intraosseous dermoid cyst of mandible (Open Journal of Stomatology 2012;2(2))
Treatment
- Enucleation, possibly curettage
- Marsupialization
Gross description
- Cystic lesion filled with keratinaceous debris and variable hair
- Specimens are often received piecemeal
Microscopic (histologic) description
- Cyst lining: orthokeratotic stratified squamous epithelium, sebaceous glands, eccrine sweat glands, variable hair follicles (only sebaceous glands is most common)
- Cyst contents: most commonly "onion skin" like flakes of keratin; cholesterol clefts, hair, nails and necrotic keratinaceous debris may also be present
Microscopic (histologic) images
Differential diagnosis
- Dentigerous cyst: cuboidal, nonkeratinizing lining
- Keratocystic odontogenic tumor: orthokeratotic variant has stratified squamous lining and may have sebaceous differentiation, but no hair, no eccrine sweat ducts / coils
- Radicular cyst: stratified squamous lining with cholesterol clefts, but no sebaceous glands, eccrine glands or hair