Intracranial midline dermoid and epidermoid cysts in children.

Abstract

Dermoid and epidermoid cysts are rare space-occupying lesions of the central nervous system. Although characterized by a slow growth rate, they are often associated with serious complications. Surgery is the only effective treatment, and radical resection of the entire cyst, whenever possible, generally succeeds in achieving a cure. Authors of large series have only occasionally reported on pediatric cases, and these reports often lack a specific analysis of those cerebral midline lesions. The authors report on the treatment of 19 patients (16 with intracranial intradural dermoid and three with epidermoid cysts located along the cerebral midline). All patients underwent surgery at the Catholic University Medical School in Rome. The patients ranged in age from 3 months to 16 years. Nine cysts were located in the posterior cranial fossa, six in the frontobasal subarachnoid spaces, two in the third ventricle, and two in the quadrigeminal plate cistern. In the cases presenting with dermal sinus tracts, attempts at resecting the dermoid cyst and the associated dermal sinus were made in a single stage to achieve an en bloc removal. In the cases without dermal sinus tracts, and in the three with epidermoid cysts, a standard craniotomy was performed to reach the lesion. There were no surgery-related deaths, and the morbidity rate was low. Total and subtotal resections were achieved in 15 and four cases, respectively; however, regrowth of the residual tumor was observed only in two of them. After repeated resection, tumor progression has not been observed. At a mean follow-up period of 92.7 months, excellent clinical results were achieved in 18 patients. Because surgery is the only effective treatment modality for these lesions, radical resection should be performed in all cases to avoid tumor recurrence; however, because the cyst capsule can adhere firmly to vital structures and attempts at its radical removal can be dangerous, subtotal resection may be a wise option in selected cases.