BIOM-16. NTRK (NEUROTROPHIC TYROSINE RECEPTOR KINASE) FUSIONS IN GLIOMA PATIENTS: A PROMISING MOLECULAR TARGET?. (12th November 2021)

• Record Type: Journal Article
• Authors: Vernadou, Anastasia; Argyrakos, Theodoros; Papadopoulou, Eirini; Rigakos, Georgios; Tsoukalas, Konstantinos; Labropoulos, Stefanos; Avgoustidou, Maria; Razis, Evangelia
• Is Part Of: Neuro-oncology. Volume 23: Supplement 6(2021)
• Page Start: vi13
• Page End: vi13
• Publication Date: 2021-11-12
• Subjects: Brain Neoplasms -- Periodicals; Brain -- Tumors -- Periodicals; Brain -- Cancer -- Periodicals; Nervous system -- Cancer -- Periodicals; 616.99481
• DOI: 10.1093/neuonc/noab196.047
• Languages: English
• ISSNs: 1522-8517

Abstract

Abstract: BACKGROUND: NTRK gene fusions are rare in gliomas (less than 2%). The use of TRK inhibitors in NTRK-fused solid tumors has generated significant clinical interest. It is likely that the unmet need for effective therapies in glioma will lead to routine testing for NTRK fusions. METHODS: We performed a retrospective review of 22 patients with malignant gliomas accrued between 2007 and 2021. We collected tumor samples from those patients and NTRK fusions were tested using either immunohistochemistry or FISH or NGS. We then evaluated their association with clinical characteristics, histology and other markers (IDH1/2 mutation, MGMT methylation, BRAF mutation, EGFR expression, ATRX expression, TERT mutation). RESULTS: Median age at diagnosis was 50 years. NTRK1 translocation was detected in 3 out of 22 patient tumors, while NTRK1 duplication was present in 1 patient (probably related to a translocation, but not proven). All NTRK1 translocations were not found in glioblastomas and their median survival was 15.8 months. On the other hand, median survival of gliomas without NTRK translocations was 11 months. In one NTRK1-translocated patient a TRK inhibitor (entrectinib) was used (for a few days), but we cannot evaluate its efficacy as the patient deteriorated and died. As far as the other biomarkers are concerned, 2 out of 3 NTRK1-translocated gliomas were MGMT methylated. CONCLUSION: NTRK fusions are rare in gliomas, as confirmed in our small sample analysis. Although adult NTRK-fused gliomas are considered to predominantly involve high-grade histology, in our study all patients had initially lower grade gliomas. NTRK alterations can be detected by different laboratory assays, but each of these approaches has specific advantages and limitations and more data are needed in order to identify the best method. For glioblastomas, NTRK fusions and TRK inhibitors are potentially a new targeted therapeutic strategy but more data are needed.