ROS1 and neoplasm: In the STARTRK1 trial, Drilon et al.39 report a pontine astrocytoma harboring an NTRK fusion that showed tumor volume reduction upon treatment with Entrectinib, a tyrosine kinase inhibitor known to target NTRK, ALK and ROS1. These encouraging results have led to a current phase I/Ib study being conducted in pediatrics to evaluate Entrectinib in primary CNS tumors (NCT02650401), which includes NTRK, ROS1, and ALK fused tumors.