Adenoid Cystic Carcinoma of the Airways:Helical CT and Histopathologic Correlation

277 rimary tumors of the trachea are rare and constitute only 2% of all respiratory tract tumors [1]. Of these, malignant tumors are more common than benign tumors and account for 60–83% in adults [2]. Adenoid cystic carcinoma, which was formerly named “cylindroma” and “adenocystic carcinoma,” occurs mainly in the salivary glands or central airways, such as the trachea and the main bronchi; it is a low-grade malignancy that is the second most common tracheal malignancy at histology (33%) after squamous cell carcinoma (48%) [3]. With the advent of MDCT, rapid scanning throughout the thorax and multiplanar reconAdenoid Cystic Carcinoma of the Airways: Helical CT and Histopathologic Correlation