ISSN: 2250-0359 Volume 3 Issue 4 2013

Dr Joyce Pascal Rozario,

ABSTRACT:Epidermoid cyst, a variant of dermoid cyst, is a benign lesion of epithelial origin, in which the cystic cavity is lined by epithelium without skin appendages. The head and neck sites most commonly affected with cutaneous cysts include the scalp (34%), neck (18%), periorbital area (17%), cheeks (including lips-16%), periauricular area (9%), and nasal area (including forehead-6%). Although a common cutaneous presentation in the head and neck region, epidermoid cysts of the maxillary sinus is an extremely rare occurrence. We report a case of epidermoid cyst of the maxillary sinus. The lesion being rare and asymptomatic often presents a diagnostic dilemma for the clinician.

Keywords: Epidermoid cyst, Dermoid cyst, Cholesteatoma

INTRODUCTION:The occurrence of epidermoid cyst in the paranasal sinuses is rare. The frontal sinus being the most common site of involvement, followed by ethmoid sinus and the least common being maxillary sinus. Epidermoid cysts manifest between the second to the sixth decade with no specific sex predilection. In 1991, Hartman and Stankiewicz reported that they found only 20 cases of cholesteatoma of any paranasal sinus(1).In 1992, Storper and Newman found only 10 such cases(2).

CASE REPORT:An eight year old apparently healthy boy, presented with history of a vague swelling below right eye and right malar region since five years. The lesion was initially small in size and had progressively grown to the present size. There was no history of discharge from the swelling, nor nasal obstruction or discharge. He did not give complaints of problems related to vision or ocular movements. History of any trauma or surgical intervention to face or head was ruled out.

On examination, a diffuse swelling was present on right malar region, extending to just below right lateral canthal region. On palpation, there were no local signs of acute inflammation, and local cutaneous sensation was normal. The swelling was firm in consistency and non tender. with no discharge. A complete blood count and erythrocyte sedimentation rate were within normal limits. Chest radiograph did not reveal any abnormality. An initial differential diagnosis of chronic inflammatory lesion like foreign body granuloma or osteogenic sarcoma was arrived at, after examining the patient, which was negated by imaging.

Computed tomography (CT scan) showed soft tissue lesion involving the inferior orbital margin with pressure erosion of bony inferior orbital wall with small calcific focus within, suggestive of epidermoid cyst. There was no mass effect on intraorbital muscles and no erosion of maxilla or extensions into pterygo-palatine fossa or masticator space or retroorbital extension.

FIGURE: CT scan showing soft tissue lesion involving the inferior orbital margin with pressure erosion of bony inferior orbital wall with small calcific focus within, suggestive of epidermoid cyst.

The lesion was approached via a subciliary approach. The lesion was seen extending deep to zygoma and into maxilla. Pressure erosion of inferior orbital margin was noted. The lesion was completely excised and the irregular infra-orbital margins was rasped. The patient made an uneventful postoperative recovery.

On gross histo-pathological examination the mass was grayish brown and had cheesy material. Microscopic examination showed skin within the underlying cyst. The cyst was lined by squamous epithelium and contained lamellated keratin. Surrounding the cyst was lymphocytic infiltrate with occasional foreign body giant cells. Chronic inflammatory reaction was seen. A diagnosis of epidermal inclusion cyst was made.