Letter to the editor

Immune therapy trials for malignant brain tumors are challenging to undertake and there are many factors, including the high expense per patient which limits the number of patients enrolled, hence curtailing the ability to demonstrate that the intervention improves clinical outcomes. Profiling the immune cell populations in peripheral blood by flow cytometry is a potentially useful tool, and hierarchical clustering analysis of the multiple cell populations measured may provide a distinct and comprehensive overview of the immune status [2]. J Immuno Ther Cancer. 2013; 1: 7–18. doi:10.1186/2051-1426-1-7 3 Fadul CE, Fisher JL, Hampton TH, Lallana EC, Li Z, Gui J, Szczepiorkowski ZM, Tosteson TD, Rhodes CH, Wishart HA, Lewis LD, Ernstoff MS. Immune response in patients with newly diagnosed glioblastoma multiforme treated with intranodal autologous tumor lysate-dendritic cell vaccination after radiation chemotherapy.