The Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy

The goal of cIMPACT-NOW is to facilitate input and consensus review of novel diagnostically relevant data and determine how such information can be practically incorporated into future central nervous system tumor classifications. While it is understood that the major impact on international brain tumor classification comes about through the WHO classification update process, it is anticipated that this additional process will “see impact” in selected tumor types and in time periods between the WHO classification updates. Thus, the cIMPACT-NOW updates are not intended to supplant the existing WHO classification, nor are they in any way part of the official WHO process; rather, the cIMPACT-NOW updates are intended to provide possible guidelines for practicing diagnosticians and information and to provide possible guideposts for future WHO classification updates. cIMPACT-NOW initially involves neuropathologists who played leading roles in the 2016 CNS WHO classification as well as a representative Clinical Advisory Panel, which will also suggest ad hoc clinical consultants for each major review topic and will review recommendations. In addition, the group plans to cycle its membership, primarily by bringing along new junior members. It is anticipated that cIMPACTNOW will solicit, circulate and evaluate suggestions for topics in at least yearly intervals and that guidelines on these topics will also be issued about once a year. Generation of these guidelines will be accomplished through a process that involves dynamic working groups, each tackling a specific topic judged to be ready for evaluation. Significantly, cIMPACT-NOW is sponsored by the International Society of Neuropathology (ISN), reflecting the central role played by neuropathologists in classifications and the substantial effect that new classifications play in the daily activities of neuropathologists. It is expected that the group will promptly publish its recommendations; after appropriate review, each guideline publication will be in Acta Neuropathologica with an accompanying commentary focusing on the neuropathological implementation of the recommendations, in Brain Pathology, the official ISN journal. cIMPACT-NOW, prompted by the quickening pace of change in the field, represents a change in the way the international neuro-oncology community approaches tumor classification. Like the official WHO classification process, however, it is hoped that cIMPACT-NOW will provide consensus guidelines that will improve clinical, experimental and epidemiological approaches to human brain tumors and that will eventually lead to a cure for these diseases.

Louis DN, Aldape K, Brat DJ, Capper D, Ellison DW, Hawkins C, Paulus W, Perry A, Reifenberger G, Figarella-Branger D, Wesseling P, Batchelor TT, Gregory Cairncross J, Pfister SM, Rutkowski S, Weller M, Wick W, von Deimling A. cIMPACT-NOW (the consortium to inform molecular and practical approaches to CNS tumor taxonomy): a new initiative in advancing nervous system tumor classification. Brain Pathol. 2017 Nov;27(6):851-852. doi: 10.1111/bpa.12457. Epub 2016 Dec 20. PMID: 27997995.

Louis DN, Aldape K, Brat DJ, Capper D, Ellison DW, Hawkins C, Paulus W, Perry A, Reifenberger G, Figarella-Branger D, Wesseling P, Batchelor TT, Cairncross JG, Pfister SM, Rutkowski S, Weller M, Wick W, von Deimling A. Announcing cIMPACT-NOW: the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy. Acta Neuropathol. 2017 Jan;133(1):1-3. doi: 10.1007/s00401-016-1646-x. PMID: 27909809.