A Rare Case Of Parotid Dermoid

Dr. Nikesh M GosraniPG RESIDENT,

IGGMC, NAGPUR

HISTORY19 yr old malec/o swelling on

right parotid regionsince 9 years

Increasing gradually

HISTORYPast history - not significant

Family history - not significant

Personal history - chronic gutka chewer

GENERAL EXAMINATIONGC- modAfebrileP-74/minBP- 120/80 mmHgNo pallor/clubbing/cyanosis/icterus/edemaNo significant cervical lymphadenopathy

Systemic ExaminationRespiratory system -NADCardiovascular system - NADGastrointestinal system - NADCentral Nervous System - NAD

LOCAL EXAMINATIONSwelling in rt parotid size 4x3cmSoft ,cystic ,mobile

non FluctuantNo s/o inflamation Overlying skin

normal

LOCAL EXAMINATIONFacial nerve normal examination b/lOral cavity -NADNose -NADEar -NAD

INVESTIGATIONSHb - 12.9 gm%TLC - 8800/mm

N-56%,L-38%,E-3%,M-3%Bld. Urea - 16 mg%Urine – N.

FNAC - inconclusiveUSG LOCAL- mild heterogenous lesion

in right parotid size 4x3x4 cm on superficial lobe

? Pleomorhic adenomaDifferential Diagnosis : Rt parotid pleomorphic

adenoma Warthins tumor Dermoid

Branchial cleft cystBranchial pouch cyst

Advice operation :superficial parotidectomy

Intraoperational findings :

Mass 4x3x4Unilocular cystOpaque grey white Dense fibrous wall

Histopathology report :Cyst wall - stratified squamousUnderlying sebaceous glandsWith hair follicless/o d=Dermoid

DiscussionAlso called Epidermal cyst.Dermoid cyst of head & neck rare (6.9% of all dermoid cyst)

Orbit 49.5%, nose 12.6%,submental & submaxillary region 23.3 % remainder 14.6%

Initially Based on pathogenesis & microscopic appearanceCongenital dermoid - teratoma type(ovaries & testes)Acquired dermoid cyst (hands & other exposed parts)Congenital inclusion dermoid (head & neck).

a.nasooptic groove

b.nose (frontonasal plate)

c.submental & submaxillary region

d.miscellaneous group(midventral or middorsal line )

DiscussionNow 4 types of Dermoid – Sequestration dermoid

Implantation dermoidTubulo dermoid

Teratomatous dermoidSequestration – inclusion of epithelium burried at line of

embryonic fusion eg; near head & neckImplantation dermoid- indriven epithelium beneath skin due to

puncture injury eg ; exposed part of bodyTubulodermoid – cyst from unobliterated portion of congenital

ectodermal duct or tube eg;thyroglossal cyst,post anal cyst,ependymal cyst in brain

Teratomatoid dermoid – from totipotent cells eg; ovary,testis

DiscussionParotid dermoid – rare entityClinicallydifficult to make diagnosisPhysical examnation – no characterstic findingsIsolated mass, near surface or within glandHistologically –keratization of squamous

epithelium, a/w skin appendages – hair follicles,sweat glands, sebaceous gland

Parotid dermoid relatively well encapsulatedSimple excision may recur so superficial

parotidectomy is advisable

ConclusionParotid extremely rareDue to rarity & absence of pathognomonic

findings , difficult to diagnose preoperativelyMust be differentiated from malignant

tumors & other cystic lesionRecur after simple excision so superficial

parotidectomy is advisable