|
Radiotherapy for supratentorial low-grade glioma and cognitive function
In a prospective phase III trial, 20 adult patients with supratentorial low-grade glioma (LGG) treated with 50.4 Gy (10 patients) or 64.8 Gy (10 patients) localized radiotherapy (RT) were evaluated with an extensive battery (i.e. 3-4 hours) of psychometric tests at baseline (before RT) and at approximately 18-month intervals (for up to 5 years) after completing RT. To allow patients to serve as their own controls, cognitive performance was evaluated as change in scores over time and all patients underwent at least 2 evaluations. We found baseline test scores below average compared with age-specific norms. At the second evaluation (i.e. approximately 18 months after radiotherapy), the groups' mean test scores were higher than their initial performances on all psychometric measures, although the improvement was not statistically significant. No changes in cognitive performance were seen during the evaluation period when test scores were analyzed by age, treatment, tumor location, tumor type, or extent of resection. Although, as a group, patients receiving high-dose RT did not have decreased cognitive function compared with the low-dose group, individually patients in the high-dose group tended to have more cognitive impairment after RT (no decrements were found in the lower dose arm). In summary, our results are consistent with those of other prospective studies (with neuropsychological evaluations completed before and after RT), which document highly stable cognitive functioning for adults with LGG after focal, moderate dose (i.e. 50.4 Gy) RT in the absence of tumor progression.
Bibliographical reference:
Paul Brown Division of Radiation Oncology, Mayo Clinic, Rochester, MN
|