Adenoid cystic carcinoma of the lacrimal sac.

Adenoid cystic carcinoma is the most common epithelial malignancy of the lacrimal gland and minor salivary glands. Its occurrence in the lacrimal drainage system is extremely rare. A 57-year-old woman presented with epiphora and a mass in the lacrimal sac, which proved to be an adenoid cystic carcinoma. Histologically, it appeared to arise from the wall of the lacrimal sac, and both the lacrimal gland and maxillary antrum were uninvolved by tumor. Despite aggressive surgical intervention, recurrence and metastasis developed. Adenoid cystic carcinoma must be considered in the differential diagnosis of epiphora.