Nasolacrimal duct obstruction secondary to lacrimal sac involvement by sebaceous carcinoma.

Sebaceous carcinoma (SC) is the third most common eyelid malignancy in Australia, and is potentially fatal. It usually presents as a nodule or diffuse eyelid thickening, and is commonly misdiagnosed. We describe a case of SC with lacrimal sac involvement, presenting with clinical features of nasolacrimal duct obstruction. At the time of endoscopic dacryocystorhinostomy (DCR), nasal endoscopy revealed a polypoid mass of the opened lacrimal sac. Biopsy of the mass showed poorly differentiated SC. The lacrimal drainage apparatus was later excised via a combined external and endoscopic approach. Conjunctival map biopsies showed extensive intraepithelial disease, which was treated with topical mitomycin C. At three-month follow-up, there was no evidence of residual disease on nasal endoscopy or repeat conjunctival biopsy.