Clinical characteristics and outcome of central nervous system tumors harboring NTRK gene fusions

PURPOSE TRK fusions are detected in less than 2% of central nervous system tumors. There are limited data on the clinical course of affected patients. EXPERIMENTAL DESIGN We conducted an international retrospective cohort study of patients with TRK fusion-driven CNS tumors. RESULTS 119 patients were identified. The median age at time of diagnosis was 4.5 years. The majority were reported to have a histology consistent with a diagnosis of high-grade glioma (HGG) (57.1%) followed by low-grade glioma (LGG) (27.7%). Pediatric patients had a better prognosis with a median overall survival of 185.5 months compared to 24.8 months in adults (p<.0001). Patients with LGG also had a better outcome when compared to HGG (p=0.0012). The objective response was 68.8% with larotrectinib compared to 38.1% for non-targeted treatment. CONCLUSIONS Children with LGG glioma had a favorable outcome compared to adult and HGG. TRK inhibitors appear to improve tumor control.