Primary Central Nervous System (CNS) tumors are a heterogeneous group of tumors arising from cells within the CNS and can be benign or malignant. Brain tumors are among the most aggressive forms of cancer. Glioblastoma (GBM), the most aggressive type of brain cancer, has a meager 5-year survival. Brain cancers are also the most common and most lethal of all pediatric solid tumors. Importantly, children with these tumors surviving into adulthood often display long-term effects of therapy, including surgery, radiotherapy, and/or chemotherapy.
Brain tumors are challenging to treat. In part to their location in the brain, these tumors are often surgically inaccessible. Additionally, owing to the presence of the blood-brain barrier (BBB), these tumors may not be exposed to systemic chemotherapy at levels required for disease control/cure. Finally, the unique developmental, genetic, epigenetic, and microenvironmental features of the brain frequently render these cancers resistant to conventional and novel treatments.
The current inability to develop effective drugs for this deadly disease is due to an incomplete understanding of brain tumor biology. Furthermore, there is a disconnect between preclinical drug development and rigorous testing in the clinic that needs to be addressed. Recent progress in genomics, along with significant advances in cancer and CNS immunology, are stimulating diagnostic and therapeutic improvements that will help advance the field of neuro-oncology. The use of liquid biopsies and advanced imaging approaches will likely provide strong diagnostic and monitoring abilities for tumor response earlier in the course of treatment. In addition, the use of advanced stratification approaches will help target therapies to those most likely to benefit while reducing the risk of treatment-related toxicities.