PROM1 and malignant colon neoplasm: For example, CD133-positive cells were detected in 0.7–6.1% (Ricci-Vitiani et al, 2007), 1.8–24.5% (O'Brien et al, 2007), 0.3–3% (Todaro et al, 2007) of primary colon cancer cells, and in 0.7–3.2% of primary pancreatic cancer cells using flow cytometric analysis (Hermann et al, 2007).