Epidermoid cyst of the brainstem in children: case-based update.

Epidermoid cysts are rare, slow growing, space-occupying lesions of early adulthood. Among the various locations, involvement of the brainstem is quite exceptional. In children, these tumors are extremely uncommon; only 4 purely intrinsic brainstem epidermoids are reported in the literature. The pathogenesis of true intraaxial brainstem epidermoid is unclear and is usually not considered in the preoperative differential diagnosis of brainstem tumors. We report 2 additional cases of brainstem epidermoid cysts occurring in children, underlining their clinical characteristics, the difficulties faced in the diagnostic work-up, and the surgical treatment adopted. These tumors pose a surgical challenge and attempts at aggressive removal of the cyst wall are fraught with increased risks of morbidity and mortality. On the other hand, cases treated more conservatively show good or excellent results with minimal complications. Neurosurgical judgment at the time of surgery is warranted to ensure maximum resection while minimizing postoperative neurologic deficits.