Metastatic acinic cell carcinoma presenting as a recurrent pituitary adenoma.

A cinic cell carcinoma is the third most common epithelial malignancy of the salivary glands. In the Armed Forces Institute of Pathology registry, acinic cell carcinoma accounts for 6% of all salivary gland tumours. It most often develops in the parotid gland (86%) and is slightly more common in females (58.8%). Acinic cell carcinoma has a more favourable prognosis than most salivary gland malignancies. However, local and regional recurrence may develop in 34%. Distant metastatic disease is rare and most often arises in the lungs and bones. Acinic cell carcinoma metastases to the brain have been reported previously. However, no cases of acinic cell carcinoma metastasizing to the pituitary gland have been reported. We present a case of metastatic acinic cell carcinoma presenting as a recurrent pituitary adenoma.