Author Affiliation: Division of Neurosurgery, Department of Surgery, The University of Alabama at Birmingham.
Gliomas are primary tumors of the central nervous system and are classified into grades I to IV according to histologic criteria. Grades I and II are low-grade gliomas and grades III and IV are considered malignant gliomas. Low-grade gliomas affect both children and adults. However, the predominant histologic type of glioma found in children is a grade I tumor, juvenile pilocytic astrocytoma, and is curable by complete surgical resection.
More problematic are the low-grade gliomas that occur in adults, referred to as grade II gliomas (LGGs). These tumors are characterized by an entirely different pattern of behavior. They are invasive and cannot be completely resected surgically; residual tumor cells are always present distal to the margin of resection no matter how extensive. Commonly, these tumors recur, eventually undergo malignant degeneration, and are ultimately fatal.1
Markert JM. The Role of Early Resection vs Biopsy in the Management of Low-Grade Gliomas. JAMA. 2012;308(18):1918-1919. doi:10.1001/jama.2012.14523