MET and neoplasm: However, the limitations of using tissue genotyping as the “gold standard” is the tumor heterogeneity which might be missed by tissue biopsies.32,33 Therefore, tumor heterogeneity can reduce overall concordance between plasma and tissue.34 Jiang et al. have shown that subjects with stage II–IV NSCLC showed more somatic mutations in plasma than tissue samples.34 One of the studies, Leighl et al,26 had a FP case in MET exon 14 that was detected by ctDNA NGS, but it was not detected by tissue genotyping.