Familial juvenile polyposis coli and colorectal cancer.

A 40-year-old mother and her 7-year-old son underwent colectomy for polyposis coli. Both colectomy specimens contained predominantly juvenile polyps. The mother's specimen also had numerous tubular adenomas and one 5-cm severely dysplastic villous adenoma without invasive carcinoma. Foci of adenomatous change in juvenile polyps were present in the son's specimen. The histologic features of both cases suggest a sequence of change from juvenile polyps to adenomatous polyps to cancer.