Adenoid cystic carcinoma of the parotid metastasising to the dura fifteen years post primary resection: A case report.

Adenoid cystic carcinoma (ACC), regardless of the primary site, is typically characterized by a long clinical course associated with a high rate of distant metastases. Intracranial metastasis of ACC is a very rare entity with only few reported cases in the literature. In this study, we report an unusual case of extra-axial intracranial metastasis of ACC in the dura. The primary parotid gland tumour was resected 15 y back. No recurrence had been detected before the occurrence of extra-axial metastasis. After surgical decompression, palliative radiotherapy was administered. To our knowledge, this is the longest interval for the development of metastases following excision of a parotid adenoid cystic carcinoma. This case can raise awareness across specialties that patients with adenoid cystic carcinoma are still at risk of developing metastases even following specialist discharge.