polyposen

Polyposen, or polyposis, describes a condition characterized by the presence of multiple polyps in mucous membranes, most commonly in the gastrointestinal tract. While most polyps are benign, a high burden of polyps increases the risk of cancer and other complications. Polyposis can be sporadic, affecting mainly the colon, or hereditary, arising from germline genetic mutations that cause multiple polyps and cancer risk.

Hereditary polyposis syndromes are the main cause of polyposis when numerous polyps are present. Notable syndromes include familial adenomatous polyposis (FAP), caused by mutations in the APC gene and typically presenting with hundreds to thousands of colonic polyps and a near-certain risk of colorectal cancer if untreated; attenuated FAP, with fewer polyps and later onset; MUTYH-associated polyposis (MAP), due to biallelic MUTYH mutations; Peutz-Jeghers syndrome, featuring hamartomatous polyps throughout the GI tract and characteristic mucocutaneous pigmentation with elevated cancer risk; and juvenile polyposis syndrome, in which multiple juvenile polyps occur in children and young adults, also increasing cancer risk. Cronkhite-Canada syndrome is a rare nonhereditary form involving GI polyposis with weight loss and other systemic features.

Diagnosis relies on endoscopic visualization and histologic examination of polyps, complemented by genetic testing when a hereditary syndrome is suspected. Management focuses on polyp removal and surveillance to detect cancer at an early stage. In hereditary conditions like FAP, risk-reducing strategies such as intensified endoscopic surveillance and, in many cases, colectomy, are common. Treatment plans are tailored to the specific syndrome, polyp burden, cancer risk, and patient age.

Prognosis depends on the underlying cause and the effectiveness of surveillance and preventive measures; hereditary polyposis generally requires lifelong monitoring due to elevated cancer risk.