A review of NTRK fusions in cancer.

ABSTRACT

The family of the neurotrophic tropomyosin kinase receptors (NTRK or TRK) is a part of the transmembrane tyrosine kinases responsible for neuronal development. The members of this receptor family are TRKA, TRKB and TRKC and they are encoded by the genes NTRK1, NTRK2 and NTRK3. Alterations of NTRK genes can induce carcinogenesis both in neurogenic and non-neurogenic cells. The prevalence of NTRK gene fusion is under 1% in solid tumors, but is highly encountered in rare tumors. The presence of NTRK 1 gene fusion is associated, in some types of neoplasia, with a favorable evolution, but the presence of NTRK 2 may be associated with a poor prognosis. The identification of cancer patients harboring NTRK gene fusions is constantly growing, especially with the advent of NTRK inhibitors. This has promisingly provided a rationale for personalized therapeutics that improved outcomes in settings with this signature.