Reply

摘要

We thank Dr Thomson for his comments regarding the evidence that regular use of 5-ASA agents is associated with some reduction in the cancer risk among patients with chronic ulcerative colitis and for mentioning the possible chemopreventive benefits from ursodeoxycholic acid in those with coexisting primary sclerosing cholangitis.It remains unclear whether these agents have intrinsic antineoplastic activity or if the benefits result from their anti-inflammatory effects alone.In general, we support the use of aminosalicylates in ulcerative colitis, but feel that it is unrealistic to expect that "primary prevention alone can avert all cases of colorectal cancer, especially in high-risk patients such as the onedescribed. Indeed, the point we were trying to emphasize is that patients with ulcerative colitis and primary sclerosing cholangitis are at such high risk for colorectal neo-plasia, that early secondary intervention is specifically warranted and that the most effective means to deal with this risk is colonoscopic surveillance or prophylactic proctocolectomy.