Mixed tumors account for about 10% of the childhood central nervous system tumors. Studies of the most common tumor, the ganglioglioma, in patients of all ages suggest that optimal therapy is total gross resection. There are few studies on these tumors in children. In our institution between 1984 and 1993, 28 children with gangliogliomas (4 of which were anaplastic) and 4 children with dysembryoplastic neuroepithelial tumors were treated and followed. Fourteen had local subarachnoid involvement. Total gross resection was usually curative, regardless of histology. Subarachnoid involvement was not indicative of a poorer prognosis.
Congenital arachnoid cysts (CAC) are benign developmental disorders. A number of theories have been proposed to explain the origin and progression to the symptomatic stage. Management strategies range from not treating the asymptomatic cysts to craniotomy, excision of cyst wall and establishment of a communication with the adjacent subarachnoid cistern or ventricle. Other lesions may resemble CAC, and can be differentiated from CAC only by a critical review of the biopsy specimen. We have reviewed our experience with true CAC and similar lesions. Based on our experience we recommend craniotomy, excision of cyst wall and establishment of a communication with an adjacent subarachnoid cistern or ventricle as the primary procedure.
Tumors caused by radiation treatment are not unkown. They may be benign or malignant. Among these, postradiation meningiomas (PRM) are considered to be a distinct entity. A case of a child who developed a PRM is presented. She received radiation therapy for a presumed thalamic glioma 11 years earlier. An unusual and interesting aspect of this tumor was its attachment to the membrane of the old subdural hematoma, following a shunting procedure. There was no dural attachment. The pathology of PRMs and meningiomas in children are discussed in light of our recent experience.
In a prospective, randomized, cooperative group trial, the value of iv vincristine and intrathecal methotrexate and hydrocortisone as adjuvant therapy to radiotherapy in children with medulloblastoma and ependymoma was evaluated. The data showed no improvement in the survival of such children when adjuvant therapy was given.
