CFP and neoplasm: Sequential in vivo assessment of the same host bearing an initial mixture of CSC (10%, YFP labeled) and non-stem tumor cells (90%, CFP labeled) demonstrated that CSCs outgrew non-stem tumor cells, with a 51.9 fold volume increase for the CSCs and a 0.92 fold increase for the non-stem tumor cells (Fig. 2B) and there was limited intermingled growth among populations (Fig. 2C, D).