FAMILIAL intestinal polyposis is a rare hereditary disease characterized by the growth of very many adenomatous polyps from the rectal and colonic mucosa. The polyposis (Fig. 1) generally develops in adolescence or early adult life, though more rarely it may occur in the first decade or after middle age. The disease appears to be inherited as a heterozygous, dominant Mendelian characteristic; thus, only an affected parent, either male or female, can transmit the disease, and then only to half the children.
Colonic polyposis is probably the most clearly defined precancerous disease known to medical practice today. Dr. Cuthbert Dukes,* who has followed the course of this disease at St. Mark's Hospital for many years, has recently (1952) reviewed 156 cases and shown convincingly that malignancy develops in one or more polyps with grim punctuality 10 to 15 years after the first symptoms of polyposis and that the expectation of life