Extra-salivary gland presentations of adenoid cystic carcinoma: A report of three cases

Adenoid cystic carcinoma (ACC) is a malignant neoplasm most commonly originating in salivary glands of the head and neck area. When ACC presents outside of these locations, the diagnosis may become more challenging. We describe three cases of ACC presenting in extra-salivary gland sites. Two cases were metastatic; in case J the initial presentation was widespread bony metastasis of unknown primary origin. The other metastatic case (case 2) was from a patient presenting with a pleural effusion and a history of previously treated metastatic pulmonary ACC. The pleural effusion cytology was unusual in that exfoliated ACC cells were present in the effusion itself, a rare occurrence. Case 3 was a primary bronchial ACC. In conclusion, ACC can present in various body sites and cytologists must consider this neoplasm when presented with a basaloid carcinoma of uncertain origin.