NEW APPROACHES TO THE CLASSIFICATION OF COLON SERRATED LESIONS
Serrated formations of the colon in modern classification are divided into three main categories: hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), traditional serrated adenoma (TSA). Despite the existing difficulties, pathologists are encouraged to make every effort to identify SSA/P, since their potential malignancy is higher than that of HP. This work is devoted to compare potential malignancy of HP and SSA/P based on the immunohistochemical profile (cdx2, beta-catenin, p53, ki67, claudin-1, -3, -4, CD44, Musashi-1). The results we obtained indicate the vague nature of the immunohistochemacal differences between HP and SSA. The nature of expression of most markers studied, indicates a lower potential malignancy of HP and SSA/P compared to TSA. The relatively high incidence of abnormal CDX2 expression suggests a significant role of alternative ways of HP and SSA/P malignization. TSA is fundamentally different from HP and SSA/P in immunophenotype, which may indicate both a higher potential malignancy of TSA and different ways of carcinogenesis of these types of polyps, despite their unification into a general group of “serrated formations”. The paper shows the absence of a statistical difference between HP and SSA / P and the fundamental difference from them TSA, which may be the basis for modernizing the classification of colon`s polyps.