A review of physical abnormalities in familial adenomatous polyposis

Familial adenomatous polyposis (FAP) is an autosomal dominant condition wherein multiple polyps may be found in the gastrointestinal tract. Initially referred to as familial polyposis coli, it has become evident that virtually all patients with FAP develop adenomas in the upper gastrointestinal tract and thus the syndrome is now termed familial adenomatous polyposis. The number of associated conditions both malignant and benign has been increasingly recognized. Some of these lesions cause morbidity and mortality in affected individuals whilst others act as important clinical markers for identifying patients not yet expressing the phenotype. These abnormalities can arise from tissues of all three primary embryonic layers and are described in this paper.