Abstract
The identification of more effective therapies for brain tumors has been limited in
part by the lack of reliable criteria for determining response and progression. Since
its introduction in 1990, the MacDonald criteria have been used in neuro-oncology
clinical trials to determine response, but they fail to address issues such as pseudoprogression,
pseudoresponse, and nonenhancing tumor progression that have arisen with more recent
therapies. The Response Assessment in Neuro-Oncology (RANO) working group, a multidisciplinary
international group consisting of neuro-oncologists, medical oncologists, neuroradiologists,
neurosurgeons, radiation oncologists, and neuropsychologists, was formed to improve
response assessment and clinical trial endpoints in neuro-oncology. Although it was
initially focused on response assessment for gliomas, the scope of the RANO group
has been broadened to include brain metastases, leptomeningeal metastases, spine tumors,
pediatric brain tumors, and meningiomas. In addition, subgroups have focused on response
assessment during immunotherapy and use of positron emission tomography, as well as
determination of neurologic function, clinical outcomes assessment, and seizures.
The RANO criteria are currently a collective work in progress, and refinements will
be needed in the future based on data from clinical trials and improved imaging techniques.
Keywords
response assessment - RANO - brain tumors - glioma
