PROM1 and cancer: Moreover, using the 5% positive cells as cut-off to distinguish between high (>5%) and low (≤5%) staining, high CD133 staining was detected in 9 (75%) of the 12 pT 1 cancers and in 10 (59%), 27 (36%) and 19 (58%) of the pt2, pT3 nd pT4 cancers, respectively and cross-tab analysis identified a significant correlation (p = 0.02) between the two parameters (Table2).