Success in treating aggressive
brain tumors like
glioblastoma multiforme and
medulloblastoma remains challenging, in part because these
malignancies overcome CNS immune surveillance. New insights into
brain tumor immunology have led to a rational development of immunotherapeutic strategies, including cytotoxic Tlymphocyte
therapies and dendritic cell
vaccines. However, these
therapies are most effective when applied in a setting of
minimal residual disease, so require prior use of standard cytotoxic
therapies or cytoreduction by surgery. Myeloablative
chemotherapy with autologous hematopoietic
cell transplantation (autoHCT) can offer a platform upon which different cellular
therapies can be effectively instituted. Specifically, this approach provides an inherent 'chemical debulking' through high-dose
chemotherapy and a graft-versus-
tumor effect through an autologous T-cell replete graft. Furthermore, autoHCT may be beneficial in 'resetting' the body's immune system, potentially 'breaking'
tumor tolerance, and in providing a 'boost' of immune effector cells (NK cells or cytotoxic T lymphocytes), which could augment desired anti-
tumor effects. As literature on the use of autoHCT in
brain tumors is scarce, aspects of
immunotherapies applied in non-CNS
malignancies are reviewed as potential
therapies that could be used in conjunction with autoHCT to eradicate
brain tumors.