Biopsy of pediatric brain stem tumors.

26 patients, average age of 7.3 years, has biopsies of a brain stem tumor. 62% of the patients presented with hydrocephalus, and ventriculoperitoneal shunts were placed 7-10 days prior to biopsy. The midbrain was biopsied 13 times, the pons 3 and the medulla 12 times. Tissue for histopathologic examination was obtained at each operation and demonstrated astrocytoma in 13 patients, glioblastoma in 6, 'no tumor seen' in 5 and ependymoma in 2. Astrocytomas were usually located in the upper brain stem, and all of the glioblastomas were located in the medulla. The operative mortality was zero, and the morbidity was largely related to increased cranial nerve deficit. All the astrocytoma patients were treated with radiation only; whereas, 4 patients with glioblastoma were treated with vincristine, CCNU and methylprednisone in addition to radiation as described by the Children's Cancer Study Group (CCG-944). 3 patients with 'no tumor' were not treated and are alive and well 15-41 months following operation. 2 patients with no tumor were treated, one as a glioblastoma multiforme, subsequently verified at postmortem examination, and one as a midbrain astrocytoma. 1 patient with astrocytoma died 3 months following operation, all the remainder are living and well 4-51 months following operation. Irrespective of the treatment, all 7 patients with glioblastoma expired within 9 months of diagnosis. The prognosis for survival for patients with brain stem astrocytoma is superior to those with glioblastoma multiforme. Specific histopathologic correlation with clinical management may lead to improved and prolonged survival for patients with brain stem glioma.