Efficacy of Screening Methods for NTRK Gene Fusions in Solid Tumors
Posted: Sunday, August 1, 2021
Peng et al, of Chongqing Medical University, China, conducted a study to determine the frequency of NTRK gene fusions in Chinese patients with solid tumors. They also sought to compare the efficacy of targeted next-generation sequencing, fluorescence in situ hybridization, and immunohistochemistry in the detection of these genetic alterations. Their findings were presented during the virtual edition of the American Association for Cancer Research (AACR) Annual Meeting 2021 (Abstract 2285).
“Next-generation sequencing [effectively helped to screen for patients] with novel or reported NTRK fusion who may benefit from NTRK inhibitor therapy. Next-generation sequencing showed good consistency with immunohistochemistry,” the investigators commented. “Further prospective study is needed to compare the impact of NTRK status identified by next-generation sequencing and immunohistochemistry on [the efficacy of NTRK inhibitors].”
Between January 2017 and June 2020, a total of 25,976 tumor samples were collected. The investigators assessed the samples using targeted next-generation sequencing. NTRK gene fusions were confirmed by fluorescence in situ hybridization analysis and/or pan-TRK immunohistochemistry.
A total of 0.2% of patients harbored one or more NTRK gene fusions. These genetic alterations were identified in 15 cancer types: thyroid (1.1%), sarcoma (0.5%), neuroendocrine (0.5%), gastrointestinal stromal tumor (0.4%), endometrial (0.4%), esophageal (0.3%), colorectal (0.3%), head and neck (0.3%), lung (0.2%), ovarian (0.2%), breast (0.1%), biliary tract (0.1%), liver (0.1%), stomach (0.1%), and other (0.03%).
Among the patients with NTRK gene fusions, 11 were further confirmed by both fluorescence in situ hybridization and immunohistochemistry and 3 were confirmed by immunohistochemistry alone. A total of 36.4% of patients had completely concordant NTRK status. Consistent results between next-generation sequencing and fluorescence in situ hybridization were observed in 45.5% of the patients. The majority of patients (71.4%) had consistent results between next-generation sequencing and immunohistochemistry. Two novel gene fusions were reported: TEX10-NTRK2 in head and neck cancer and PTPN22-NTRK1 in ovarian cancer.
Disclosure: The study authors reported no conflicts of interest.