Adenoid Cystic Carcinoma Developed from the Parotid Gland to the Ear Lobe of a Young Woman.

Adenoid cystic carcinoma (ACC) is a relatively rare malignant tumor. It is more common in women than in men and typically develops in the lacrimal, salivary, and breast glands. ACC of the external auditory canal (EAC) is exceedingly rare, and its invasion into the ear lobe is even more unusual.