NTRK1 and metastatic neoplasm: Ingenuity Pathways Analysis (IPA) of the 55 gene set showed over-representation for canonical pathways categorized under Cellular Growth, Proliferation and Development descriptors; and the most over-represented was the Stem Cell Pluripotency pathway (p<0.01; Figure 1); genes in this pathway showing copy number aberrations in the metastatic tumors were PIK3CA, SOX2 and the neurotrophin receptor NTRK1.