These analyses are conducted to generate hypotheses only and will need to be validated in additional patients or studies. Statistically, joint effects will also be explored, but are unlikely to have sufficient power to identify such interactions. Assuming that half the sample size of 35 patients are positive for a particular measure (i.e. detection of tumor -specific antibodies at a particular post -vaccination time point) and that all have died, we will have 80% power for a log rank test conducted with α=0.05 to detect a survival hazard ratio of 2.6 comparing patients with a positive and negative measure. 21.6 Statistical Analysis of L ongitudinal Immunologic Measures All statistical analyses have been proposed and will be undertaken by the study statistician. Our laboratory have devoted considerable energy to co -developing and co- validating the high -throughput immunologic assays outline d above for monitoring TTRNA -specific CD8+ or CD4+ T cells in PBMCs from patients with GBM. The reproducibility of these assays in our hands ensures that they can be reliably used for monitoring of changes over time. Of interest in this study is 1) whether there exists a difference in the number of tumor specific T cells as measured by CFC (Cytokine Flow Chemistry) after TTRNA -xALT and TTRNA -DC vaccination and 2) whether there exists a change in a given immunologic measure over time with each patient servin g as their own control. For (1) we will use simple two -sample t -tests for means derived from each group for each parameter. Assuming 35 patients will received DC + xALT therapy during the Phase II trial, we will have 80% power to detect a difference betw een groups equal to approximately 1.79 standard deviations of the immune response (i .e., coefficient of variation = 0.557) at the α=0.05 level (2- tailed). For (2), we assumed for the power calculations , that measurements of immune response parameters will be normally distributed and correlated (r=0.5). All samples will be run in triplicate and the mean of the triplicate will be used for analysis. All statistical tests will be conducted at the 0.05 level of significance. In all assays proposed above, a paired t -test will be conducted unless assumptions required for conducting a t -test are not satisfied. In such cases, a non -parametric Wilcoxon signed rank test will be conducted. The difference detectable w ith a paired t-test from the mean at baseline in this study for a given patient is shown below: Coefficient of Variation Test Percent change from baseline mean detectable (80% Power) Percent change from baseline mean detectable (90% Power) <0.10 Luminex, DTH, Serum Titers, 2.56% 6.14% <0.15 CFC, Proliferation 3.67% 4.50% Immunological response evaluations for baseline values will be conducted on a blood sample draw 24 hours before administration of HDC and prior to DC + xALT therapy and on a subsequent blood draw obtained two weeks after the third immunization. Immunologic response evaluations will also be performed from peripheral blood obtained prior to each vaccination.