PECAM1 and neoplasm: To obtain a macroscopic understanding of the distribution pattern of α-SMA-positive CAFs, we conducted a 3D histological analysis through the coimmunostaining of α-SMA and CD31 in two PNET samples (The tumor depicted in Fig. 2a underwent 3D histological analysis, as shown in Fig. 2e, while the tumor from Fig. 2b is presented in Fig. 2f).