Supratentorial low-grade gliomas comprise a group of primary central nervous system neoplasms with characteristics of neuroglial cells (i.e., astrocytes and oligodendrocytes) and relatively low anaplastic potential, although through time they tend to behave more aggressively. Immediate surgical intervention and subsequent radiation therapy are advocated by some workers; at present, however, it remains unclear whether early intervention prolongs survival or changes the natural history of the disease, especially in those patients who present with a seizure and a normal interictal examination.