title: Hyperplastic polyps and serrated adenomas: precancerous lesions with mixed immunophenotype.
abstract: Our immunohistochemical study wants to be a contribution to clarifying the adenoma-carcinoma sequence and serrated pathway of colorectal carcinogenesis. Thus, we performed immunohistochemical analysis of hyperplastic polyps (HP), serrated adenomas (SA), and classical adenomas (tubular adenomas - TA and tubulovillous adenomas - TVA) and carcinomas developed from adenomas (CA) using expression of p53, Ki-67, c-myc, APC, MSH2 and Ets-1 proteins. Because of correlation of the expression of these proteins, we propose several immunophenotypes, which show modifications along the known carcinogenetic mechanisms. Along the adenoma-carcinoma sequence we noted an increase in the expression of p53, Ki-67, c-myc and Ets-1, and a decrease in APC expression. The majority of TAs and TVAs are characterized by p53+÷Ki-67+, p53+÷c-myc+, p53+÷APC+, and Ets-÷p53+, Ets-÷Ki-67+ immunophenotypes. The majority of HPs and SAs are Ets-÷p53-, Ets-÷Ki-67+, Ets-÷c-myc+, APC+÷MSH2-. In approximately 1÷3 of the hyperplastic polyps and serrated adenomas, we noted that the decrease in expression of MSH2 is associated with an increase in the expression of p53, c-myc, Ki-67, and Ets-1. Thus, we can conclude that a group of hyperplastic polyps and serrated adenomas display similar immunohistochemical characteristics to tubular and tubulovillous adenomas, which delineates a group of precancerous lesions that can develop via mixed carcinogenic pathways.
authors: Department of Anatomy, University of Medicine and Pharmacy of Targu Mures, Romania. papzsuzsa@yahoo.com
authors: Zsuzsanna
authors: Z
authors: Pap
authors: Z
authors: Z
authors: Pávai
authors: L
authors: L
authors: Dénes
authors: Klara
authors: K
authors: Brînzaniuc
authors: I
authors: I
authors: Jung
mesh_terms: D000236:Adenoma / Q000235:genetics / Q000473:pathology*; D000328:Adult; D000368:Aged; D003111:Colonic Polyps / Q000235:genetics / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology*; D005260:Female; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000235:genetics / Q000473:pathology*