AMP case report: Comprehensive molecular characterization of an aggressive infant-type hemispheric glioma with a novel PRKAR2A::ALK fusion
October 2026—Infant-type hemispheric glioma (IHG) is a molecularly defined pediatric high-grade glioma first recognized in the 2021 World Health Organization classification of tumors of the central nervous system. These tumors arise predominantly within the first year of life and are characterized by large hemispheric masses and frequent receptor tyrosine kinase (RTK) gene fusions, most commonly involving ALK, NTRK1/2/3, ROS1, or MET.