TTF1 and neoplasm: The surgical specimen of the intestinal mass following laparoscopic surgery showed poorly differentiated carcinoma with local sarcomatoid differentiation, infiltrating the whole layer with visible nerve and intravascular tumor thrombus, with IHC markers CK (+); CK7 (+); CK20 (−); TTF‐1 (+); vimentin (+); CD34 (vessel+); CD31 (vessel+); ETS related gene (ERG) (vessel+); CD117 (−); Dog‐1 (+); P63 (−); desmin (−); smooth muscle actin (SMA) (−); S‐100 (−); and Ki‐67 (70%+) (Fig 2).