Management of serrated adenomas and hyperplastic polyps.

The benign serrated architecture of the hyperplastic polyp has now been recognized in morphologically similar lesions with potential for transformation to colorectal carcinoma: the sessile serrated adenoma (SSA), traditional serrated adenoma (TSA), and mixed polyp. These represent a group of serrated polyps with potential to evolve into colorectal cancer through a different molecular pathway than the traditional adenoma-carcinoma sequence, called the serrated pathway. Genetic characteristics involve a defect in apoptosis caused by BRAF and K-ras mutations that create distinct histologic characteristics of atypia in serrated architectural distortion of the crypts. An evidence-based algorithm for the clinical management of this polyp has yet to be determined. Current recommendations suggest these lesions be managed similar to conventional adenomas. The histology of serrated polyps is reviewed, as well as the common characteristics, and implications for treatment and surveillance.