Neuroimaging: diagnosis and response assessment in glioblastoma.

Glioblastoma is the most common primary malignant brain tumor; standard initial treatment includes a combination of radiation and temozolomide, and treatment at recurrence often includes the use of antiangiogenic agents. Characterization of tumor at initial diagnosis, assessment of response, and ability to distinguish viable tumor from treatment effects are ongoing challenges in neuroimaging. Progress has been made with the new Response Assessment in Neuro-Oncology criteria, and new imaging modalities and combinations continue to be evaluated to further improve our ability to characterize glioblastomas at all points during their disease course.