Guidelines and Recommendations
Best Practice Recommendations and National Resources in the Diagnostic Work-up of Inflammatory Myopathies
(from the 2025 Neuropathology in Practice Forum, Canadian Association of Neuropathologists Annual Meeting, Banff, AB, October 24, 2025)
This document summarizes the recommendations of the Canadian Association of Neuropathologists with respect of the diagnostic work-up of inflammatory myopathies. These recommendations are based on the current medical literature and presentations and discussions during the 2025 Neuropathology in Practice Forum.
Immunohistochemical markers of inflammatory pathways and autophagy have become standard for the myopathological characterization of inflammatory myopathies within a clinico-sero-pathological classification. The present recommendations summarize current markers and try to give a tiered approach to their implementation ranging from core recommendations to additional options. These recommendations are not designed to shape an approach to muscle biopsy evaluation in general, but to guide work-up in cases of a reasonable suspicion of an inflammatory myopathy with the aim of classifying the subtype of inflammatory myopathy. Exclusion of other types of pathologies relies on general myopathological evaluation and clinico-pathological correlation.
Finally, a listing of national resources is also included for reference.
Submitted respectfully,
Invited Speakers/Primary Authors:
Dr. Peter Schutz MD PhD Dr. Benjamin Ellezam MD PhD
Vancouver General Hospital Centre Hospitalier Universitaire Sainte-Justine
University of British Columbia University of Montreal
Moderator/Editor:
Dr. Robert Hammond MD
London Health Sciences Centre
Western University
January 2026
Canadian Association of Neuropathologists Recommendations for Molecular Testing of CNS Tumours
The recommendations below provide an overview of best practices as of January 2024 in the diagnosis of select tumours of the CNS including diffuse and circumscribed gliomas, glioneuronal tumours, ependymomas, and medulloblastomas. These recommendations have been reviewed and approved at a national level by the Canadian Association of Neuropathologists. This document is expected to evolve over time in response to continued scientific study and clinical experience.
The document also serves to describe the minimum expectations for Canadian diagnostic laboratories to support the diagnosis of brain tumours to the current standards of the WHO, including the immunohistochemical, molecular and cytogenetic tests detailed below. For optimal workflow and timely patient care, it is recommended that de-centralized testing be maximized where possible, although methylation profiling may require a more centralized approach.Munoz, D. G. et al. Molecular Testing of Central Nervous System Tumours – Recommendations of the Canadian Association of Neuropathologists. Can. J. Neurol. Sci. J. Can. des Sci. Neurol. 1–17 (2024) doi:10.1017/cjn.2024.332.