PECAM1 and neoplasm: Intimal sarcomas belong to tumors of uncertain differentiation in the World HealthOrganization classification of tumors of soft tissue and bone.4 In our case, the tumor onimmunohistochemical grounds showed only positive vimentin staining, which indicates amesenchymal origin; however, the endothelial markers CD31 and CD34 were negative inmalignant cells excluding an endothelial derivation.