Identification of NTRK fusions in pediatric mesenchymal tumors

Pediatr Blood Cancer. 2017 Aug;64(8). doi: 10.1002/pbc.26433. Epub 2017 Jan 18.


Background: NTRK fusions are known oncogenic drivers and have recently been effectively targeted by investigational agents in adults. We sought to assess the frequency of NTRK fusions in a large series of pediatric and adolescent patients with advanced cancers.

Procedure: Genomic profiles from 2,031 advanced cancers from patients less than 21 years old who were assayed with comprehensive genomic profiling were reviewed to identify NTRK fusions.

Results: Total of nine cases (0.44%) harbored NTRK fusions, including novel partners. Four of these cases were in children less than 2 years old for which infantile fibrosarcoma was considered as a diagnosis, and two harbored the canonical ETV6-NTRK3. The remaining cases carried other diagnoses, at least one that carried the diagnosis of inflammatory myofibroblastic tumor.

Conclusions: NTRK fusions occur in a subset of young patients with mesenchymal or sarcoma-like tumors at a low frequency, and are eminently druggable targets via either investigational agents or approved drugs.

Keywords: IFS; IMT; NTRK1-3; kinase fusion; mesoblastic nephroma; sarcoma.

MeSH terms

  • Adolescent
  • Child, Preschool
  • Discoidin Domain Receptor 2 / genetics*
  • Female
  • Gene Expression Profiling
  • Humans
  • In Situ Hybridization, Fluorescence
  • Infant
  • Infant, Newborn
  • Male
  • Oncogene Proteins, Fusion / genetics*
  • Receptor, trkA / genetics*
  • Soft Tissue Neoplasms / genetics*
  • Young Adult


  • Oncogene Proteins, Fusion
  • DDR2 protein, human
  • Discoidin Domain Receptor 2
  • Receptor, trkA