Molecular classification of patients with unexplained hamartomatous and hyperplastic polyposis.

Context: Significant proportions of patients with hamartomatous polyposis or with hyperplastic/mixed polyposis remain without specific clinical and molecular diagnosis or present atypically. Assigning a syndromic diagnosis is important because it guides management, especially surveillance and prophylactic surgery.

Objective: To systematically classify patients with unexplained hamartomatous or hyperplastic/mixed polyposis by extensive molecular analysis in the context of central rereview of histopathology results.