Dermoid cyst Definition:
- Dermoid cyst is a benign embryonic tumor of ectodermal origin.
- Cystic/mature teratoma: Dermoid cyst which contains tissue from all 3 germ-lines
Terminology:
- Dermoid cyst, dermoid, epidermoid
- Epidermoid cyst: synonym for both a dermoid cyst and an epidermal cyst.
ICD code:
- D279
Pathogenesis:
- Origin: arise from tissue dispersed during embryonic development due to the entrapment of ectodermal elements along the lines of embryonic closure.
- Composition:
- Capsule: coarse, the surface smooth and shiny.
- Contents: Pronounced variability of 3 germ-line derivatives with regard to their differentiation
- Often contain hair, teeth, adnexa, bones, or fat (contents are oily at 37 ° C, pasty at room temperature → keratinized debris can often be expressed as a cheesy mass after incision)
- Microscopy: The following structures are randomly mixed up and embedded in loose connective tissue:
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- +/- Granulomatous inflammation: granulomatous inflammation with foreign body giant cells develops when the contents of the cyst penetrate the soft tissue
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Dermoid cyst types as per the Localization:
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Clinical manifestations:
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Complication:
- Malignant degeneration is possible → carcinomas of the squamous epithelium, malignant melanomas or sarcomas.
Dx:
- CT: dermoid of CNS appear non- contrasting and hypodense → can grow around the surrounding brain tissue.
- MRI: show a signal intensity similar to that of CSF (confused with enlarged cisterns)
- Diffusion-weighted imaging sequence (DWI-MRI): appear light and the liquor appear dark are used for the differential diagnosis.
Ddx:
- Epidermal cysts, but they usually have not been around since the birth
- Subcutaneous hemangiomas
- Gliomas and other congenital malformations of the central nervous system
- Other ovarian tumors
Rx:
- Should be excised in toto.
- Must be taken into account that connections to deeper-lying structures (orbit or neural structures) even with superficial localization on the skin.
Mnemonic of Cystic teratoma – Dermoid cyst
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MCQs:
- Dermoid arises from?
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- Pluripotent cell
- Totipotent cell
- Ectoderm
- Mesoderm
- What is the most probable diagnosis based on the given image?
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- Dermoid cyst
- Sebaceous cyst
- Lipoma
- Hemangioma
Also read:
Also Watch:
- Dermoid Cyst: 5-Minute Pathology Pearls
- Dermoid cyst scalp excision by Dr. Pandiaraja
- Dermoid Cyst Ablation 2D
References:
- 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.
- Sorenson EP, Powel JE, Rozzelle CJ, Tubbs RS, Loukas M. Scalp dermoids: a review of their anatomy, diagnosis, and treatment. Childs Nerv Syst. 2013 Mar;29(3):375-80.
- Brownstein MH, Helwig EB. Subcutaneous dermoid cysts. Arch Dermatol. 1973 Feb;107(2):237-9.
- Pryor SG, Lewis JE, Weaver AL, Orvidas LJ. Pediatric dermoid cysts of the head and neck. Otolaryngol Head Neck Surg. 2005 Jun;132(6):938-42.