Table 2 shows a low level of ABCB1 mRNA already in mild/moderate dysplasia which is maintained at a low level throughout carcinogenesis. Comparing ABCB1 mRNA levels, a significantly lower mRNA level was found in the mild/moderate adenoma, severe adenoma and CRC tissues (Table 2) as compared to morphologically normal tissue from the same individuals. There was no correlation between the ABCB1 mRNA levels and age, gender or Duke’s stage of the carcinoma (Dukes stage A (n = 19), stage B (n = 47), and stage C (n = 29)). This evidence concerns the gene ABCB1 and adenoma.