Metastatic Intracranial Adenoid Cystic Carcinoma with Unknown Primary: Case Report and Review of Literature.

Adenoid cystic carcinoma (ACC) is an epithelial malignancy comprising approximately 8-10% of all salivary gland tumors. Intracranial ACC without a known primary is an extremely rare pathobiological event. Only 13 cases have been reported in available literature. We report a case of a rare intracranial ACC in a 35-year-old gentleman presenting with features of raised intracranial pressure. Patient had a lesion in the right parieto-occipital lobe and underwent gross total decompression. There was no evidence of any primary after a thorough systemic evaluation. In the postoperative period, he showed a good clinical improvement and was recurrence free at follow-up of 18 months. We also discuss and review the existing relevant literature.