Primary Squamous Cell Carcinoma Arising From an Epithelium-Lined Cyst of the Lacrimal Gland

In Brief A 66-year-old man presented with a slowly enlarging, nontender left orbital mass of 2 months’ duration. CT and MRI showed a left lacrimal gland mass with enhancement and internal irregularity of cystic structures. Histopathologic analysis of the biopsy specimen revealed a squamous cell carcinoma arising from an epithelium-lined cyst. The patient underwent left orbital exenteration followed by radiation treatment. No evidence of tumor recurrence was observed after a follow-up of 30 months. We believe this primary squamous cell carcinoma may have arisen either from preexisting lacrimal duct cyst (dacryops) with areas of squamous metaplasia or, less likely, from a choristomatous epithelium-lined cyst of the lacrimal gland. Although rare, this entity should be included in the differential diagnosis of cystic lesions of the lacrimal gland. The clinical, radiologic, and histopathologic findings of a primary squamous cell carcinoma arising from an epithelium-lined cyst within the lacrimal gland are described.