Interestingly, [18F]TRACK uptake into muscle tissue was also elevated by 15%, however, only after 30 min and diminished after 60 min which is different from the effect in tumor and BAT tissue attributing maybe to different intracellular ATP levels to compete for binding with [18F]TRACK or different dimerization forms of the oncogene Trk versus the muscular Trk. This evidence concerns the gene NTRK1 and neoplasm.