Steatocystoma Simplex of the Orbit: Expanding the Differential for Pediatric Eye Masses.

Steatocystoma simplex (SS) is a rare cutaneous disorder that often presents as a single benign cyst, most commonly in adults. Due to overlapping clinical features, SS is often mistaken for dermoid cysts until histopathological evaluation is performed and a diagnosis is established. We present a case of a presumed orbital dermoid cyst in a pediatric patient that was ultimately identified as SS, suggesting a possible congenital origin. A 20-month-old boy presented with a painless, mobile mass of the left upper eyelid that was first noted after minor trauma. Imaging with ultrasound and computed tomography demonstrated a well-circumscribed cystic lesion, most consistent with a dermoid cyst. Anterior orbitotomy with excision of the mass and subsequent histopathological evaluation yielded a squamous epithelial-lined cyst with associated sebaceous lobules and an eosinophilic cuticle consistent with SS. The postoperative course was uncomplicated, and no recurrence has been observed. SS of the orbit is rare and resembles other common cystic lesions; therefore, diagnosis relies on histopathological evaluation following surgical excision. Literature is limited, as only two other pediatric patients have been reported to have a similar presentation, both without associated systemic findings or family history. This case highlights the importance of including SS in the differential diagnosis of pediatric orbital masses. Increased recognition of this entity may improve diagnostic accuracy and guide appropriate management of orbital lesions in children.