Hyperplastic polyposis syndrome: a call for broader diagnostic criteria

Background Hyperplastic Polyposis Syndrome (HPS) is a rare disease characterized by multiple or large hyperplastic polyps and carries an approximately 40% lifetime colorectal cancer risk. Although a genetic basis has not been established, HPS is believed to be a heritable syndrome and is diagnosed by clinical criteria as set forth by the World Health Organization (WHO). Based on clinical experience, we hypothesized that WHO criteria may be narrowly restrictive and misses some patients with an increased malignancy risk.