Neurocognitive Outcomes After Whole Brain Radiation Therapy for Hematologic Malignancies

Neurocognitive failure will be defined as the first cognitive failure on 2 or more of the following tests: the Hopkins Verbal Learning Test Revised Total Recall, Delayed Recall and Delayed Recognition; the Controlled Oral Word Association; and the Trail Making Test Part A or B. The rate of neurocognitive failure and its 95% confidence interval (CI) will be calculated. The cumulative incidence approach may be used to estimate the median time to neurocognitive failure to account for the competing risk of death. May use the Aalen-Johansen estimator of the cumulative incidence function.

Assessed using European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire - Core 30/Brain Neoplasm 20. The rates of improvement and worsening will be calculated. The rate of deterioration will be calculated. Also, Wilcoxon signed rank test or paired t-test will be used to compare the scores between baseline and after radiation at 2 months.

Will explore radiographic changes on standard-of-care MRI scans that are suggestive of radiation toxicity. Radiographic changes will be considered in the context of radiation treatment plans. Correlation of radiographic changes with radiation dose will be performed for hypothesis generation. Spearman correlation coefficient may be used to assess the correlation between radiographic changes and radiation dose.

Neurocognitive outcomes at different time points will be summarized using descriptive statistics. Changes overtime on neurocognitive outcomes may be analyzed using generalized linear models for the repeated measures. May compare the neurocognitive outcomes of the patients to a similar cohort of patients that were not treated with Memantine or other medications indicated to improve memory and cognitive function (example the RT arm of RTOG 1114). Will amend the protocol to include the details on which cohort of patients to be compared to, variables to be used for matching the two patient cohorts, and method to be used for matching once decided to proceed with the comparison.