Low-grade glial tumors: are they all the same?

The most common diagnosis for supratentorial brain tumors in children is a form of low-grade glioma. In addition to being a diagnosis on its own, this term has become a general category that encompasses many specific diagnoses. Advances in immunohistochemistry and pathology classification schemes have led to the recognition of these diverse pathologies. Even though the numbers of any given tumor type are small, the question has been raised as to whether different pathologies require different treatments. We reviewed the published articles on treatment and outcomes for all pathologies included under the heading "low-grade glioma" to answer this question. Once intervention is deemed necessary, attempted complete surgical resection remains the mainstay of treatment for all diagnoses. Surgically accessible recurrences are also best managed with repeat resection. Unresectable residuals or recurrences can be treated with adjuvant therapies. The only pathologic subgroups that may benefit from more aggressive up-front treatment are the grade II astrocytomas. Radiation is reserved for older children, and chemotherapy protocols are favored in younger children. Although the data from adult radiosurgical studies are promising, data for the pediatric population are not yet available. Many small lesions and small residuals remain unchanged for many years.