Adenoid cystic carcinoma: an unusual neurosurgical entity.

Adenoid cystic carcinoma, or cylindroma, usually presents in the salivary glands or in the upper respiratory passages. We report an unusual case of adenoid cystic carcinoma in a 45-year-old woman who presented with a three-year history of progressive right trigeminal sensory palsy, most pronounced in the second division. There was, in addition, a right trigeminal motor palsy and a partial right 6th nerve palsy. CT scanning showed only a small soft tissue mass spanning an enlarged right foramen ovale. Solid adenoid cystic carcinoma was resected from Meckel's cave via a middle cranial fossa approach. A subsequent biopsy of the right maxillary antral mucosa found tumor tissue. We concluded that the tumor originated in the maxillary antrum and spread posteriorly along the infraorbital nerve to enlarge in the foramen ovale. Radiation to a total of 5,000 cGy was given. At 22 months there was neither radiographic nor clinical evidence of recurrence. At 30 months, the development of unsteady gait signalled the presence of recurrent tumor extending backwards from Meckel's cave into the right cerebello-pontine angle.