Distinct secreted Frizzled receptor protein 1 staining pattern in patients with hyperplastic polyposis coli syndrome.

Context: Patients with hyperplastic polyposis coli syndrome are thought to harbor precursor lesions of a proposed hyperplasia-carcinoma pathway in colorectal cancer, but morphologic recognition of such lesions remains difficult. Hypermethylation of the secreted Frizzled receptor protein 1 gene on chromosome 8p12 is one of the earliest molecular alterations in colorectal carcinogenesis, potentially disrupting the Wnt signaling cascade of cellular growth control.

Objective: To determine if hyperplastic polyps from patients with hyperplastic polyposis coli syndrome show a distinct immunohistochemical expression pattern for mismatch repair proteins and secreted Frizzled receptor protein 1 compared to their sporadic counterparts.