Familial juvenile polyposis coli. A clinical and pathologic study of a large kindred.

A kindred with familial juvenile polyposis coli is described. Of 92 family members, 26 have had symptoms consistent with polyposis, and a definite diagnosis of polyposis has been made in 19. Two family members have developed colorectal carcinoma before age 40 yr. The lesion of juvenile polyposis is a characteristic nonneoplastic polyp that is distinct from the neoplastic lesion of adenomatous polyposis. Patients with this disorder develop symptoms at an earlier age than those with adenomatous polyposis. Both variants of polyposis appear to have a dominant pattern of inheritance. Patients with juvenile polyposis who present in infancy are likely to have severe symptoms and complications. Although the premalignant potential of the juvenile polyp remains in doubt, there may be an increase risk of gastrointestinal cancer in these patients and their families.