ENG and neoplasm: Pimonidazole is a nitroimidazole which specifically undergoesreduction and binds the thiol groups of proteins and amides in hypoxiccells, resulting in the formation of adducts which can be detectedby an antipimonidazole antibody.14 Tumorvasculature was assessed by the mRNA expression of CD105 (endoglin),a marker for tumor vasculature in proliferating solid tumors,15 and the blood vasculature endothelial markerCD-31 staining.