relationship between colonic bilharzial polyposis and colorectal cancer

We studied 222 patients suffering from intestinal Bilharziasis and / or colorectal cancer compared to other cancerous diseases as well as other controls. CEA in the sera of Bilharzial patients was increased in colitis and it was double the normal value in the polyp form. Its level in the neoplastic precancerous Bilharzial polyps was twice higher than those with Bilharzial polyps and less than in colorectal cancer associated with Bilharziasis. Non-Bilharzial group had either normal levels of CEA or significantly lower levels than the corresponding Bilharzial disease This study is strongly suggesting the presence of a relationship between Bilharziasis and colorectal cancer