The low-grade glioma debate: evidence defending the position of early radiation therapy.
From the preceding supporting evidence, the following conclusions can be drawn: Supratentorial LGGs are a pathologically diverse group of CNS neoplasms whose natural history is primarily dependent upon histologic subtypes. The observed survival of all histologic subtypes of supratentorial LGGs are statistically significantly worse than that of an age- and sex-matched control population. Moderate-dose postoperative RT appears to improve survival in, and may cure, a subset of patients with supratentorial nonpilocytic LGG, particularly in those in their 30s and older. Multiple shaped localized treatment fields should be utilized because whole brain radiation is both unnecessary and associated with greater toxicity. Patients with supratentorial LGGs are usually neurologically "intact" but do exhibit cognitive impairment. Neurologic, functional, cognitive, and affective status do not appear to be negatively impacted by modern postoperative RT in adults with supratentorial LGG. Therefore, all adult patients with histologically verified supratentorial low-grade nonpilocystic astrocytomas (diffuse fibrillary astrocytoma, mixed oligo-astrocytoma, or oligodendroglioma) should routinely receive postoperative RT. Localized treatment fields should be employed. The optimum dose of radiation within the range of 4,500 to 6,480 cGy has yet to be determined.
Shaw
E G
EG
Division of Radiation Oncology, Mayo Clinic, Rochester, Minnesota, USA.
D001254:Astrocytoma / Q000532:radiotherapy*; D001932:Brain Neoplasms / Q000532:radiotherapy*; D005500:Follow-Up Studies; D005910:Glioma / Q000532:radiotherapy*; D006801:Humans