I am delighted to be given the opportunity to introduce the special issue of Brain Tumor Pathology, volume 40, no.2. Papers in this issue were invited from symposia and oral presentations during the 40th Annual Meeting of the Japan Society of Brain Tumor Pathology. This meeting was actually performed as the hybrid meeting of on-site (at Kawagoe, Saitama, on May 27 and 28, 2022) and a virtual.

The main theme of this meeting was “Brain Tumor Pathology Considered from the Spatiotemporal Axis—The 40-year legacy of the society and the new WHO 2021-.” We had four symposia in this meeting, focusing on the 2021 CNS WHO classification.

To contribute to the theme, we invited three distinguished guest speakers.

First, David Louis, MD (Benjamin Castleman Professor of Pathology at Harvard Medical School, Pathologist-in-Chief at Massachusetts General Hospital, Leader of the Mass General Brigham Enterprise Laboratory Service) gave us a lecture entitled as “WHO CNS5: climbing up the other side of the valley”, and participated in the question and answer time via internet from Boston. His talk included FAQs (frequently asked questions), which was very helpful for routine practice of diagnostic pathology. Second, Charles G. Eberhart, M.D., Ph.D. (Professor of Pathology and Oncology, C.A. Wilson and MK. Whitener Professor of Ophthalmology, The Johns Hopkins University School of Medicine) came to Japan under the difficult circumstances of Covid-19 pandemic, and provided us a special lecture, “Comprehensive profiling of experimental models to exploit metabolic vulnerabilities in pediatric brain tumors”. Third, Dr. Hideyuki Saya (President of Japanese Cancer Association, Fujita Health University Cancer Center) talked about “Trend of basic cancer research and its expansion to brain tumor research” in the Educational Lecture. In addition, Dr Toshihiko Wakabayashi (Former President of the Japan Society of Brain Tumor Pathology) gave us a 40-year Memorial Lecture.

Finally, I would express special thanks to the Japan Society of Brain Tumor Pathology for publishing these excellent papers which were originally presented during the 40th Annual Meeting. I deeply appreciate the cooperation of all the authors who took time for submission. I hope these papers will be rewarding and contributing to deepen the understanding of the advance in Brain Tumor Pathology.

President, The 40th Annual Meeting of the Japan Society of Brain Tumor Pathology