ECM in the TRS of iCCA is characterized by de novo deposition of TnC, POSTN, and OPN. After the evaluation of the peritumoral tissue, we turned to the matched bulk tumor to see if ECM protein accumulation was quantitatively and qualitatively different in the TRS between MetS and non-MetS iCCAs. This evidence concerns the gene SPP1 and infantile convulsions and choreoathetosis.