PROM1 and neoplasm: Regarding the qualitative and semi-quantitative evaluation of the CD133 immunoreaction pattern, different types of subcellular immunostaining localization were detected, as follows: exclusively membrane and luminal staining in less than 50% of the entire tumor area in 22 cases (36.6%), luminal membrane and cytoplasmic staining in less than 50% of the tumor area in nine cases (15%), only luminal membrane staining in more than 50% of the tumor area in 11 cases (18.3%) and luminal membrane and cytoplasmic staining in more than 50% of the tumor area in 16 cases (26.6%) (Figure 5 and Figure 6).