Thus, we conclude that true adenomatous polyps are uncommon in northern Nigeria, and appear in patients more than 20 years old (fig. 7). The commonest type of rectal polyp is the juvenile polyp. Next in importance is the schistosomal polyp, which is seen at an earlier age here than in Egypt. These two histologic types together account for three quarters of all the rectal polyps, and appear mostly before the age of 20 years. While the schistosomal polyp in Zaria looks a little different histologically from that seen in Egypt, neither seems to have a malignant potential. There appears to be no relationship between these polyps and colorectal carcinoma, which is relatively uncommon in this region.