More recently, RTK and MAPK fusions were reported in pediatric cases (including infants) with a DNA‐methylation proven MC of pleomorphic xanthoastrocytomas (PXA) (ALK, ROS1, NTRK2, and NTRK3 fusions) as well as in the novel MC of glioneuronal tumors, not otherwise specified (NOS), subtype A (ALK, MET, NTRK1, NTRK2, NTRK3, or RAF1 fusions) [11, 12, 13, 14, 15, 16]. The gene discussed is ROS1; the disease is pleomorphic xanthoastrocytoma.