Immunohistochemical Study of Colorectal Polyps with Antibodies against CEA, CA19‐9, CA125, CA15‐3 (DF3), PCNA and p53

Abstract: We analyzed the expression of CEA, CA19‐9, CA125, CA15‐3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19‐9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15‐3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19‐9, CA15‐3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19‐9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15‐3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15‐3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15‐3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas.