Xiao et al. compared the oncogene expression of schistosomiasis adenomatous polyps, schistosomiasis nonadenomatous polyps and colorectal cancer and found that the expression rate of protooncogenes such as Bcl-2 and CK–20 was higher in adenomatous polyps than in nonadenomatous polyps, and the expression rate of the tumor suppressor gene p27 was significantly lower (p < 0.001). This evidence concerns the gene BCL2 and schistosomiasis.