Brainstem Gliomas: Classification, Growth Patterns, and Prognosis

ABSTRACT

Brainstem glimas are common intracranial tumors in young age and have dismal prognosis despite the advance in diagnostic and treatment modalities. The purpose of this study is to classify the brainstem gliomas by growth patterns and to correlate the growth patterns with histological findings. With these results,we have studied further to verify the prognostic factors in brainstem gliomas. Sixty four patients with brainstem gliomas were treated between May, 1989 and March, 1997. For the location of brainstem gliomas, 41 cases were in pons, 13 cases in medulla, 8 cases in midbrain, and 2 disseminated cases. Operations were performed in 44 cases of these lesions which were focally enhanced type or had exophytic growth patterns. Histological diagnoses were low grade gliomas in 22 cases and high grade gliomas in 21 cases. Among them, radiotherapy was performed in 39 patients with diffuse or disseminated type. Among operated pateints, seven were treated with Gamma Knife radiosurgery for focal residual lesion. Diffuse types were more common in pons. Exophytic or focal types were common in medulla and midbrain. High grade glioma was more common in diffuse type and low grade glioma was common in exophytic or focal type. We concluded that the favorable prognostic factors are long duration of symptoms(>2mos), exophytic type, low grade glioma, and radiotherapy treatment.