Ectopic ventricular recurrence of an epidermoid cyst in the middle fossa.

We present the first case of ectopic ventricular recurrence of an epidermoid cyst in the middle fossa with confirming histological characteristics. A 51-year-old woman presented with an epidermoid cyst in the middle fossa and underwent complete resection. On the 6-month surgical follow-up MRI, a nodular lesion was detected in the frontal horn of the left lateral ventricle without evidence of recurrence at the primary site. The patient underwent transcortial tumor resection. Results of histological studies confirmed that the lesion was an epidermoid cyst similar to the primary lesion. This is a case report of the cerebrospinal fluid spread of an epidermoid cyst, which strengthens the case for special care at the time of surgery to prevent spread of the lesion.