Adenoid cystic carcinoma of the lacrimal gland with wide and severe myoepithelial differentiation.

Adenoid cystic carcinoma (ACC) of the lacrimal gland is the second most common epithelial tumor for which different biologic courses can be predicted by histologic criteria. Three main types of growth patterns, cribriform; tubular; and solid have been identified. Tumors with solid components frequently follow a more aggressive clinical course and show worse prognosis than those with other patterns. We herein report a case of ACC with wide and severe myoepithelial differentiation arising from the lacrimal gland and presenting with aggressive clinical behavior. Postoperative radiotherapy may be the treatment of choice to control residual lesions and provide long-term survival even in the case of incomplete resection. Despite extensive surgery and radiation therapy, the prognosis of these tumors, especially with solid components, remains extremely poor. Accurate diagnosis is important because tumor histopathology is generally believed to be the most significant factor in patient survival.