NTRK1 and neoplasm: Within the context of NMTC, these activating stimuli could range from growth factors to metabolites (e.g. lactate) and inflammatory molecules (e.g. danger-associated molecular patterns and pro-inflammatory cytokines) produced by the tumor microenvironment, triggering either receptor tyrosine kinases, metabolic receptors, toll-like receptors or cytokine receptors expressed by follicular thyroid (tumor) cells (39, 40, 41).