The model begins with a cohort of age 30 individuals with familial adenomatous polyposis and a total colectomy. They progress linearly through stages until they die or reach age 80. Perceived disease state is clinically tracked by endoscopies with biopsy, while the true disease state corresponds to the underlying biological disease progression. Surgery can be offered at stage III, stage IV, or cancer, depending on the management strategy. Individuals may die from surgical complications, duodenal cancer, or from other causes. Stages are based on Spigelman criteria.